13

votes

new NYT article on red meat

Answered on September 12, 2014
Created April 07, 2013 at 11:10 PM

http://www.nytimes.com/2013/04/08/health/study-points-to-new-culprit-in-heart-disease.html?ref=health&_r=0

Thoughts?

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 13, 2013
at 10:37 PM

Eating food will end you. :)

7a6529ea25b655132fe58d793f95547a

(2030)

on April 13, 2013
at 09:39 PM

Great review, thanks Stabby. So basically scale back on the meat, fish, veggies, dairy, grains, and......wait...oh shit.

Fb67dc30cead043d1d13ea503a3044dc

(3280)

on April 12, 2013
at 04:57 AM

Yes, exactly. I pointed that quote out specifically because it mentions GMO mice, which we aren't -- I wasn't clear. I was thinking, Ok, but what do these mice have to do with humans?...but that I was still going to watch for further studies.

E4069040201c3591b9b774df6ed9cad4

(80)

on April 11, 2013
at 11:47 PM

I find that statement puzzling, inasmuch as his organization - Weston A. Price Foundation - advises not drinking fluoridated water. On what evidence basis does Masterjohn propose that individual, isolatable components of food cannot - categorically - be agents of disease or health? With fructose, we know that to be false. It is also plausible that carnitine -> TMAO also be an agent of disease.

2e6e673ce3eb647407d260d4d57a731b

(1021)

on April 11, 2013
at 06:51 PM

"choline (and derivatives) definitely promote brain function but possibly at the cost of future heart disease." assuming you mean choline helps the brain develop and function more properly possibly at the expense of heart health, well there's nothing wrong with that. quality over quantity.

96440612cf0fcf366bf5ad8f776fca84

(19413)

on April 11, 2013
at 02:02 PM

But humans aren't genetically modified, and humans aren't mice. These are merely models that might or might not shed light on some mechanism, which might be valid in those specific types of mice, but not the general population of humans. Case in point: mice can eat raw grains - we cannot.

96440612cf0fcf366bf5ad8f776fca84

(19413)

on April 11, 2013
at 02:02 PM

Yes Matt, but there may be other factors in grassfed meat absent from CAFO, and vice versa. I certainly wouldn't expect cattle confined to live in their own waste and fed expired candy with wrappers, and other inappropriate feed to be as beneficial to humans as those free to roam, consume forage, and be exposed to sunlight. Would you? Just looking at the livers of CAFO chicken versus pastured chicken tells you a whole lot.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 11, 2013
at 01:01 AM

So meat increases TMAO but it's not uniquely elevating http://www.westonaprice.org/blogs/cmasterjohn/2013/04/10/does-carnitine-from-red-meat-contribute-to-heart-disease-through-intestinal-bacterial-metabolism-to-tmao/ And difference between vegetarians and omnivores at baseline probably have to do with other factors http://perfecthealthdiet.com/2013/04/lessons-from-the-latest-red-meat-scare/ Regarding whether or not vegetarians will produce less TMAO from carnitine, I think that they probably do to some extent, though Chris cast doubt on the idea. And it's kind of a moot point.

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 10, 2013
at 10:14 PM

Hey Kali, if you wouldn't mind I'd like to see any papers you have on protein restriction extending life span.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 10, 2013
at 05:13 PM

But maybe just not more than the beneficial nutrients in meat (like carnitine!) reduce the risk. Though the best policy might be to eat red meat but cook it carefully to get the best of both worlds. It's funny, the study that the authors of this new paper post to prove that red meat causes heart disease contradicts their thesis.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 10, 2013
at 05:12 PM

But maybe just not more than the beneficial nutrients in meat (like carnitine!) reduce the risk.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 10, 2013
at 05:11 PM

But maybe just not more than the beneficial nutrients in meat (like carnitine!) reduce the risk. Damn epidemiology...so speculative and given so much importance.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 10, 2013
at 05:09 PM

Good catch, that part bugged me. The better argument would be that if you look at the epidemiology on red meat, it's only the processed red meat that's associated with heart disease risk, and vegetarians don't consume processed meat, so it would be more likely that this (amongst other things like the healthy user effect) explains the lower rates. Though Chris doesn't believe that processed meat is bad so I guess that prevents that. Fried bacon has the most reactive HCAs of any meat I've seen (though following this reasoning harsh cooking methods used on fresh meat would also raise risk...)

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 10, 2013
at 04:13 PM

Jim B, yeah I noticed that about the epidemiology he cited, like the Epic-Oxford study, which did find decreased CVD in vegetarians. He switches from saying vegetarianism isn't associated with less heart disease to vegetarianism isn't associated with lower mortality.

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 10, 2013
at 04:12 PM

Jim B, yeah I noticed that about the epidemiology he cited, like the Epic-Oxford study, which did find decreased CVD in vegetarians. He switches from saying vegetarians don't have less heart disease to vegetarians don't have lower mortality.

7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 10, 2013
at 04:07 PM

Also, to be fair to the authors, they aren't saying that red meat causes heart disease, just that it increases the risk through the described mechanism in the mice, and the biomarker, TMAO, corresponds to increased risk in the patients that were sampled. I believe one of the authors remarked that steak is too tasty to give up, but that he might cut back a little. The researchers/Kresser are more on the same page than not.

7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 10, 2013
at 04:04 PM

1. "The Epidemiological Evidence is Inconsistent" - doesn't support Kresser, either. 2. "What's in the Gut?" (whoop) - I said the same thing in this thread before Kresser - PH loves me and showers me in adulation. Anyway, mostly nice work by Chris, but disingenuous to imply there should be "gut controls". They are definitely needed, but gut characterization has just really started in earnest. Patience everybody, we'll get there.

7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 10, 2013
at 03:29 PM

Not aware. I just follow it casually.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 11:25 PM

Sorry not "it" there are some that seem to be very potent and some that aren't. Still offering to e-mail anybody that paper. :)

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 11:24 PM

Oh ok, cool. Well according to the first paper it has quite a bit of it, and the evidence that those fish are harmful is downright scant. It would be interesting to see this new group compare TMAO increases between red meat and some kinds of fish to see which is more potent.

F5a0ddffcf9ef5beca864050f090a790

(15515)

on April 09, 2013
at 06:10 PM

@Matt - LOL at real meat.

E4069040201c3591b9b774df6ed9cad4

(80)

on April 09, 2013
at 05:02 PM

As you're probably aware, "the benefit of high HDL" is under serious questioning in the cardiology research community, as is the entire cholesterol hypothesis.

70c75942b975919dfbed8dddbd767b60

(289)

on April 09, 2013
at 04:19 PM

+1 I think this may be yet another case of misplacing the blame. When your metabolism is damaged as with SAD, many good things may appear to harm you. But removing them may do more or different kinds of harm.

70c75942b975919dfbed8dddbd767b60

(289)

on April 09, 2013
at 03:49 PM

@Matt well, I think cholesterol can be shown to contribute to arterial plaques too. Lower the cholesterol and incidence of plaque will decrease too. I'm not saying TMAO isn't harmful, I'm saying we don't know enough yet, and we should have a bit of caution before deciding to make life changes based on this - this research is really in its infancy at this point. Fools rush in.

70c75942b975919dfbed8dddbd767b60

(289)

on April 09, 2013
at 03:35 PM

@thhq Even a researcher who has zero vested interest may still make a procedural error. There's a difference between criticizing for dishonesty/conflict-of-interest and criticizing for technical mistakes. Not that I'm saying their guilty of the latter either; I don't have enough info, which is why I kept it as an open question.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 12:12 PM

Google says fish simply have TMAO in their flesh and bacterial action reduces it back to volitile and smelly TMA.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 12:05 PM

Why would raw meat make a difference? Heck, I'm just pleased that the study used real meat as opposed to just a supplement.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 11:18 AM

@Mscott, now that you mention it, they didn't vary the dose of carnitine... hmm...

Bf57bcbdc19d4f1728599053acd020ab

(5043)

on April 09, 2013
at 07:44 AM

Plus one for the good news aspect.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 03:51 AM

I could e-mail it to you. [email protected] if you don't want to share your addresses on the forum.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 03:48 AM

thanks Matt. I think the mechanism is that bacteria in the fish convert carnitine and choline, you'll both have to read the 1999 paper I guess.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 03:45 AM

Thanks Matt. I think the mechanism is that bacteria in the fish convert carnitine and choline, you'll both have to read the 1999 paper I guess. I can e-mail it to you. [email protected] if you would rather not post your addresses to the site

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 03:43 AM

Possibly, though my paper used like half a pound of meat. Would 8 hours be enough time to generate TMAO from half a pound of meat, absorb it, and then excrete it in urine? That's one thing I wonder about. If this new study is right the levels rapidly increase after only a couple hours, so some of it would get excreted pretty quickly. Maybe. Haha, hard to say.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:38 AM

And they protonate the N-oxide! Not going to happen at physiological pH! Argh!

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:36 AM

I'm not sure the mechanism of why fish produces so much TMA, what precursor is present... dunno.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:35 AM

They've stuck heavy hydrogens onto the trimethylamine portion of carnitine, so when it's metabolized, they end up with heavy trimethylamine (oxide).

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:34 AM

I don't have access right now to articles (or I can't be bothered to log into the university proxy), but I'll take a peak at the article you reference later.

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 09, 2013
at 03:20 AM

Maybe it's an issue of dose. I don't have the full text of your paper, but it seems like the studies demonstrating increased TMAO use large amounts of red meat. If it's is anything like supplemental choline, which this animal study (http://www.ncbi.nlm.nih.gov/pubmed/2723829) noted slightly increased TMA and TMAO excretion at doses of choline smaller than 7 mmol/kg body wt, but dramatically increased TMAO at 15 mmol/kg bw, Matt may be on to something with his edit about absorption playing a role.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:04 AM

Carnitine is carnitine, grass-fed or not. The same response occurs with or without meat.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 02:58 AM

...more than other foods. And that paper definitely shows that supplements and fish have a large effect, why wouldn't red meat then? You can see how I thought that 2A must have been due to the supplement then.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 02:57 AM

Thanks for your input. I wasn't sure of that, I thought that 2A might also be from the supplement, because they're both TMAO, but if you're sure that the test for TMAO wouldn't also pick up ones formed from the stable isotope-labeled supplement then I guess the steak did raise it. Question: why do you think that the vegan in 2A had much lower fasting levels (0) than any of the other vegans in the study? 2C. And what's wrong with the first study I cited? It's only looking at urinary TMAO, but if it's absorbed from dietary carnitine then the levels in urine should at least be increased...

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 02:30 AM

Meat most definitely increases TMAO.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 02:27 AM

Stabby, I'm not surprised that plasma levels of TMAO (Figure 2C) are similar in both groups (its a waste product, and eliminated via urine, I wouldn't expect it to be too high in even the meat eaters). Just look at 2A. The TMAO rise is only due to the steak, the d3-TMAO rise is only due to the isotopically labeled carnitine administered.

A08b210e4da7e69cd792bddc1f4aae4b

(1031)

on April 09, 2013
at 12:51 AM

@Matt, I'll say it again, these guys, seriously?! http://paleohacks.com/questions/186043/how-do-you-reconcile-the-fact-that-paleo-views-seem-to-directly-contradict-the-vi/186299#186299 I'm just feeling scratchy today, I need to go climb a tree!

Medium avatar

(39831)

on April 09, 2013
at 12:51 AM

Is the proposed mechanism whereby CVD incidence is increased merely lipid peroxidation? If so, isn't this just a drop in the oxidative stress bucket that is only relevant in those consuming insufficient antioxidants?

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 12:48 AM

Thanks for that, now I'm even more confused. Which ones to believe? That study has quite a few differences between the groups that don't have much to do with meat, but it does have the advantage of being of a longer duration. I guess I'll just have to wait and see what Chris Masterjohn says about it to see if he makes things more clear.

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 09, 2013
at 12:11 AM

Nice stabbing Stabby, I was hoping you'd comment. BTW This study suggests red meat may increase TMAO (http://www.ncbi.nlm.nih.gov/pubmed/17022649) as determined by an H1 NMR of urine at least.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 11:23 PM

So maybe I should change my position to say that we don't have evidence that meat is uniquely elevating to TMAO because many vegans at baseline had levels comparable to the omnivores, and TMAO in urine actually seems to be higher after many plant foods in the older study. Many of which barely have any choline as well. Or maybe I should just wait for Chris Masterjohn's article to actually explain all of this stuff. But for now, yeah, there's n=1 (selected evidence that vegans can have 0 TMAO in serum and much that contradicts that, and much evidence that meat isn't uniquely elevating of TMAO

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 11:22 PM

though carnitine, choline and fish are.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 11:22 PM

So maybe I should change my position to say that we don't have evidence that meat is uniquely elevating to TMAO because many vegans at baseline had levels comparable to the omnivores, and TMAO in urine actually seems to be higher after many plant foods in the older study. Many of which barely have any choline as well. Or maybe I should just wait for Chris Masterjohn's article to actually explain all of this stuff. But for now, yeah, there's n=1 evidence that vegans can have 0 TMAO in serum and much that contradicts that, and much evidence that meat isn't uniquely elevating of TMAO

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 11:12 PM

Actually I'll probably agree that some TMAO is omnivores is absorbed, obviously because it's in the urine in my first study, however what this means for plasma levels is hard to say. And why is TMAO in urine after eating bread and many fruits and vegetables so much higher in urine in the first study? The only real evidence that we have that vegans have 0 TMAO in plasma is from one selected vegan when most of the pooled ones (2C) are actually pretty comparable with many of the omnivores except for some outliers (probably the heavy fish eaters). Sorry I might be rambling a bit :P

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 10:56 PM

Oh but the rise in TMAO from taking carnitine supplements is supposed to be negligible in vegans according to 2A, yet in 2C they have quite a bit of it. I'm thoroughly confused by this study, heh. But I still don't have reason to think that red meat increases TMAO, I know that much.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 10:53 PM

in the omnivore, but we don't know if that's due to fish consumption which -actually has been demonstrated to increase TMAO by quite a bit-. It's curious that they only selected one omnivore representative for their graph? Why not pool all of them? Also in 2C vegans appear to have fasting levels much higher than 0, yet they're supposed to have none (2A), so should I assume that's after the carnitine challenges with the supplements? All I'm getting from this is that omnivores have a greater increase than vegans in response to supplements, not that eating meat causes increases levels.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 10:52 PM

in the omnivore, but we don't know if that's due to fish consumption which -actually has been demonstrated to increase TMAO by quite a bit-. It's curious that they only selected on omnivore representative for their graph? Why not pool all of them? Also in 2C vegans appear to have fasting levels much higher than 0, yet they're supposed to have none (2A), so should I assume that's after the carnitine challenges with the supplements? All I'm getting from this is that omnivores have a greater increase than vegans in response to supplements, not that eating meat causes increases levels.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 10:46 PM

The first study I posted demonstrated that meat doesn't increase TMAO levels but fish, carnitine supplements, and choline supplements did. And this new paper always used carnitine supplements, any time they eat meat they also took supplements, and indeed the omnivores had higher levels because of their gut microbes, but nowhere in the study do they demonstrate that meat by itself an increase it. Correct me if I'm wrong but Figure 1A appears to show an omnivore with a baseline of 0 TMAO until he takes the carnitine. Then there's 2A which appears to show TMAO being slightly higher...

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 10:17 PM

Dunno, they show both serum and urinary TMAO is higher in omnivores than in vegans. Seems like meat is a likely cause.

Ebb10603524dd22621c1155dd7ddf106

(19150)

on April 08, 2013
at 09:54 PM

stabb-y-rific .

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 09:48 PM

Not quite. TMAO is known to contribute CVD, it's not a guess. We have mouse models that support that. TMAO also correlates with high CVD rates in humans. That of course says nothing about the source of TMAO!

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 09:46 PM

LOL, a single study and you've found the new villian? TMAO via carnitine? Oh brother.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 09:43 PM

Email the authors, you might get a copy. That, or find your local library or university with a subscription.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 09:21 PM

Nice. I just posted my take on it too.

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 09:15 PM

Even worse than the atherosclerosis...will be the triumphant smugness of the vegans.

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 08:19 PM

@Matt That's an abstract and the full text is behind the paywall for me...

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 07:56 PM

Seems like we'll have all the paleo gurus weighing in on this study shortly! Twitter has lit up with folks wanting their take.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 07:54 PM

@Lumifer, malamute posted it below, here it is again: http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.3145.html

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 07:48 PM

@Leah Chemistry is a science :-) The same chemicals (e.g. carnitine) from Soylent would the the same as the same chemicals from acorn-fed bacon. However Soylent would have different chemicals (=nutrients) in different proportions compared to that acorn-fed bacon.

Medium avatar

(10611)

on April 08, 2013
at 07:38 PM

It sounded to me like they had steaks for breakfast. I wouldn't be getting out the pitchforks and gasoline when the lead research scientist is a steak-eater.

10121ac7b6beb99c0fbfbf1522c50adb

(1193)

on April 08, 2013
at 07:27 PM

I see what you're saying, but by that logic, nutrients from Soylent would be the same as nutrients from a high quality strip of bacon with regards to the body's response. If that's what you're implying, I respect that.

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 07:16 PM

Yes, in agreement with Matt, Dr. Eckel's association with the AHA just means he's interested in the subject of CAD. One cannot infer that he's invested in a particular hypothesis.

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 07:10 PM

What constitutes "aberrant gut flora"?

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 06:38 PM

Matt, do you have a link to the pape text? I'm rather distrustful of the press retellings of studies...

618fc5298c4a96b817c4918c795a875f

(1217)

on April 08, 2013
at 05:24 PM

yes to the vegetable garden! Growing your own food is a great way to integrate with your diet on an intimate level, even if all you have the time to grow is herbs. It is also a pretty good money saver - I never buy arugula or lettuces, because at this point the grow wild in my garden

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 05:02 PM

There is possibly difference in administering L-carnitine in isolation vs. administering it in the presence of cofactors in the meat.

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 05:00 PM

We don't know what the atherosclerosis profile was for plains tribes.

Ebb10603524dd22621c1155dd7ddf106

(19150)

on April 08, 2013
at 04:49 PM

LOL, no. Even if red meat is shown to directly increase TMAO and atherosclerosis, it would still be a different and unique kind of evil, separate from the many evils of soy. Although, funny enough, soy contributes to this discussion too, as it's the most common source of lecithin in SAD after meat.

B6fb8f55070f5390bd87a03b025f5bde

(60)

on April 08, 2013
at 04:23 PM

So we're agreed: red meat is the new soy.

Ebb10603524dd22621c1155dd7ddf106

(19150)

on April 08, 2013
at 04:15 PM

I'm not suggesting that. You were suggesting that others who talked about gut flora were suggesting that, and I attempting to clarify what they likely meant. :-)

B6fb8f55070f5390bd87a03b025f5bde

(60)

on April 08, 2013
at 04:06 PM

I understand that you're suggesting that optimizing your gut flora (by eating more veggies, fruits, cultured foods, or supplementing with probiotics) will "produce less (or none) of TMAO" but there's no evidence of that. What there is evidence of is that red meat has a peculiar effect in the creation of a particular kind of bacteria in the human gut which (through TMAO) leads to heart disease. Exogenous choline consumption does create TMAO and leads to heart disease, at least in mice, and likely in humans: http://www.ncbi.nlm.nih.gov/pubmed/21475195

B6fb8f55070f5390bd87a03b025f5bde

(60)

on April 08, 2013
at 03:57 PM

Interestingly this study provides yet more evidence against the long debunked lipid hypothesis and saturated fat being the cause of heart disease. However red meat may be out as an optimized protein source. While we're on it, it's mostly protein restriction (intermittent or otherwise) that is largely responsible for life extension and autophagy (numerous citations available upon request). High protein is not healthy, though it may be sexy by optimizing muscle mass. High fat, low carb, adequate protein is optimal.

Ebb10603524dd22621c1155dd7ddf106

(19150)

on April 08, 2013
at 03:53 PM

*anyone who posts that this study is about optimized gut flora...will somehow prevent TMAO's effect on heart plaque has not read the study* First, I think anyone who states that is implying that optimized gut flora will produce less (or none) of TMAO, not that TMAO does or doesn't do what the latest study claims. Finally, the metabolites of carnitine are choline, TMAO, and betaine (per the study). Saying choline creates TMAO does not seem to be correct.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 03:22 PM

@eddieosh, so what? It's not a conflict of interest. Unlike many nutirtion studies, so many are funded by assoications with vested interests (low-carb high-protein study? probably funded by beef/pork/chicken/dairy producers...)

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 03:20 PM

It was conducted with isotopically labeled carnitine as much as anything. As Lumifer pointed out, it is an effect due only to carnitine.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 03:19 PM

I wouldn't even call it a speed limit sign, it's making conclusions with very isolated simplified systems, nature is never that simple.

96bf58d8c6bd492dc5b8ae46203fe247

(37227)

on April 08, 2013
at 03:11 PM

Exactly, thhq. As much as I love beef, I wouldn't make it 3 days trying to eat it and nothing else. I think those are very silly conversations. Besides, if I could have only one food I'd choose potatoes, preferably in chip form!

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 03:04 PM

The article explicitly identified *carnitine* as the problem. So no, the cut of the meat doesn't matter.

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 03:03 PM

Anyone has a link to the full study text? Pop-media renditions of studies tend to screw up on a very regular basis...

Medium avatar

(10611)

on April 08, 2013
at 01:46 PM

Read The Oregon Trail if you get a chance. In the Northern Plains there was fresh buffalo nearly every day for the hunting season, possibly as long as 4-6 months. The rest of the year was dried meat.

Medium avatar

(10611)

on April 08, 2013
at 12:22 PM

I didn't see this article as a blanket endorsement of veganism. Just another turn in the road, and this is a speed limit sign

Medium avatar

(10611)

on April 08, 2013
at 12:18 PM

The "if you just had one food" questions here still puzzle me. This article points out potential flaws in making that one food red meat. We're omnivores so that we can slant our diet to what's available at any time. TMAO aside, a lot of red meat constipates me.

1edb06ded9ccf098a4517ca4a7a34ebc

(14952)

on April 08, 2013
at 10:21 AM

not all are different. Some are different, and some are the same but both have the largest amounts of the C9 isomer.

A08b210e4da7e69cd792bddc1f4aae4b

(1031)

on April 08, 2013
at 09:36 AM

Credibility Alert: "Dr. Robert H. Eckel, a professor of medicine at the University of Colorado and a past president of the _American Heart Association_".

141171c0810650168d82601d85cfa5a3

(415)

on April 08, 2013
at 07:40 AM

It looks like they were using the synthetic CLA supplements with the wrong isomers and ratios in that study. Better to get CLA from real food. http://www.marksdailyapple.com/cla-supplements/

508a4ebd259022f415326f7a6baec00c

(482)

on April 08, 2013
at 06:36 AM

Two thumbs up!!

508a4ebd259022f415326f7a6baec00c

(482)

on April 08, 2013
at 05:36 AM

Good point on different cuts. Good point on the quality of the meat and where it came from. I would assume it came from a factory farm.

19acef0aed67ef8dc1118d8e74edb349

(2954)

on April 08, 2013
at 05:01 AM

Inuit must have been dropping like flies.

1edb06ded9ccf098a4517ca4a7a34ebc

(14952)

on April 08, 2013
at 01:23 AM

Yeah I know about those studies. Here's a different one with different mechanism for causing sickness. http://www.ergo-log.com/clatransfattyacids.html

1edb06ded9ccf098a4517ca4a7a34ebc

(14952)

on April 08, 2013
at 01:21 AM

I already knew about those studies. Here's a new one.http://www.ergo-log.com/clatransfattyacids.html

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 08, 2013
at 01:16 AM

Foreveryoung- it's not so simple as that: http://paleohacks.com/questions/173925/does-cla-really-cause-elevated-blood-sugar#axzz2PnxZtPwY

1edb06ded9ccf098a4517ca4a7a34ebc

(14952)

on April 07, 2013
at 11:51 PM

FYI- the beloved CLAs are worse than trans fatty acids if you are insulin resistant. Just sayin

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19 Answers

13
Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 09:21 PM

I posted this on the Time article. edit: ** (first paragraph might not be right, see comments section. The 2nd and 3rd I still stand by) **

That's all nice but it's missing an important fact: TMAO levels aren't elevated in humans by eating meat http://www.ncbi.nlm.nih.gov/pubmed/10456680 only by carnitine supplements, choline supplements, and eating some kinds of fish. Fish contains it, but I'm guessing that in meat the carnitine isn't exposed to gut microbes until it's digested and then shortly after it's absorbed into the blood stream with little exposure to the microbes, not enough to significantly impact levels in the blood. But this isn't the case for carnitine supplements that are all out in the open and exposed to microbes from the start. And this new study didn't show that meat increased TMAO levels, there was consumption of meat but only accompanied by carnitine supplements, which actually have been demonstrated to increase TMAO levels.

So am I to expect Time to come out and tell people that eating fish causes heart disease, and to stay away from choline and carnitine supplements because they will get you? I hope not, there isn't really any evidence that fish causes heart disease despite its potent effects on TMAO levels, in fact most correlations are inverse http://www.ncbi.nlm.nih.gov/pubmed/21914258 If TMAO was so important then fish would cause heart disease, wouldn't it? Maybe the heart disease patients with high TMAO levels that they looked at were eating a lot of fish because after getting heart disease they heard that eating fish was good for their hearts and that explains the association? Maybe poor kidney function results in chronically high TMAO levels in response to fish consumption and is also associated with heart disease? Is high serum carnitine a marker for insulin resistance because insulin can't store carnitine and it builds up in the blood? Lots of questions to ask. And those genetically modified mice in the study that took the carnitine supplements may not be a relevant model for humans.

Also the recent meta-analysis for red meat and coronary heart disease only implicated processed red meat like bacon and sausages, not fresh red meat like steak and roasts http://www.ncbi.nlm.nih.gov/pubmed/23001745 Though there was a weak positive correlation with diabetes risk, so maybe your recommendations for red meat are right. Or maybe it's just a problem with overcooking it which can be inflammatory, or maybe it's the fries and soda that people tend to have with their red meat. Who knows? In any case all of this isn't really convincing.

I'm also adding this http://www.ncbi.nlm.nih.gov/pubmed/11529691 L-carnitine prevents atherosclerosis in rabbits. Though maybe they don't have the right gut bacteria.

Also nice post Mscott.

Ebb10603524dd22621c1155dd7ddf106

(19150)

on April 08, 2013
at 09:54 PM

stabb-y-rific .

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:34 AM

I don't have access right now to articles (or I can't be bothered to log into the university proxy), but I'll take a peak at the article you reference later.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 11:23 PM

So maybe I should change my position to say that we don't have evidence that meat is uniquely elevating to TMAO because many vegans at baseline had levels comparable to the omnivores, and TMAO in urine actually seems to be higher after many plant foods in the older study. Many of which barely have any choline as well. Or maybe I should just wait for Chris Masterjohn's article to actually explain all of this stuff. But for now, yeah, there's n=1 (selected evidence that vegans can have 0 TMAO in serum and much that contradicts that, and much evidence that meat isn't uniquely elevating of TMAO

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 11:22 PM

though carnitine, choline and fish are.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 12:48 AM

Thanks for that, now I'm even more confused. Which ones to believe? That study has quite a few differences between the groups that don't have much to do with meat, but it does have the advantage of being of a longer duration. I guess I'll just have to wait and see what Chris Masterjohn says about it to see if he makes things more clear.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 10:56 PM

Oh but the rise in TMAO from taking carnitine supplements is supposed to be negligible in vegans according to 2A, yet in 2C they have quite a bit of it. I'm thoroughly confused by this study, heh. But I still don't have reason to think that red meat increases TMAO, I know that much.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 10:17 PM

Dunno, they show both serum and urinary TMAO is higher in omnivores than in vegans. Seems like meat is a likely cause.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 02:57 AM

Thanks for your input. I wasn't sure of that, I thought that 2A might also be from the supplement, because they're both TMAO, but if you're sure that the test for TMAO wouldn't also pick up ones formed from the stable isotope-labeled supplement then I guess the steak did raise it. Question: why do you think that the vegan in 2A had much lower fasting levels (0) than any of the other vegans in the study? 2C. And what's wrong with the first study I cited? It's only looking at urinary TMAO, but if it's absorbed from dietary carnitine then the levels in urine should at least be increased...

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 11:22 PM

So maybe I should change my position to say that we don't have evidence that meat is uniquely elevating to TMAO because many vegans at baseline had levels comparable to the omnivores, and TMAO in urine actually seems to be higher after many plant foods in the older study. Many of which barely have any choline as well. Or maybe I should just wait for Chris Masterjohn's article to actually explain all of this stuff. But for now, yeah, there's n=1 evidence that vegans can have 0 TMAO in serum and much that contradicts that, and much evidence that meat isn't uniquely elevating of TMAO

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 12:12 PM

Google says fish simply have TMAO in their flesh and bacterial action reduces it back to volitile and smelly TMA.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 03:43 AM

Possibly, though my paper used like half a pound of meat. Would 8 hours be enough time to generate TMAO from half a pound of meat, absorb it, and then excrete it in urine? That's one thing I wonder about. If this new study is right the levels rapidly increase after only a couple hours, so some of it would get excreted pretty quickly. Maybe. Haha, hard to say.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 03:51 AM

I could e-mail it to you. [email protected] if you don't want to share your addresses on the forum.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 02:30 AM

Meat most definitely increases TMAO.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 11:12 PM

Actually I'll probably agree that some TMAO is omnivores is absorbed, obviously because it's in the urine in my first study, however what this means for plasma levels is hard to say. And why is TMAO in urine after eating bread and many fruits and vegetables so much higher in urine in the first study? The only real evidence that we have that vegans have 0 TMAO in plasma is from one selected vegan when most of the pooled ones (2C) are actually pretty comparable with many of the omnivores except for some outliers (probably the heavy fish eaters). Sorry I might be rambling a bit :P

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 10:52 PM

in the omnivore, but we don't know if that's due to fish consumption which -actually has been demonstrated to increase TMAO by quite a bit-. It's curious that they only selected on omnivore representative for their graph? Why not pool all of them? Also in 2C vegans appear to have fasting levels much higher than 0, yet they're supposed to have none (2A), so should I assume that's after the carnitine challenges with the supplements? All I'm getting from this is that omnivores have a greater increase than vegans in response to supplements, not that eating meat causes increases levels.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 03:45 AM

Thanks Matt. I think the mechanism is that bacteria in the fish convert carnitine and choline, you'll both have to read the 1999 paper I guess. I can e-mail it to you. [email protected] if you would rather not post your addresses to the site

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 10:53 PM

in the omnivore, but we don't know if that's due to fish consumption which -actually has been demonstrated to increase TMAO by quite a bit-. It's curious that they only selected one omnivore representative for their graph? Why not pool all of them? Also in 2C vegans appear to have fasting levels much higher than 0, yet they're supposed to have none (2A), so should I assume that's after the carnitine challenges with the supplements? All I'm getting from this is that omnivores have a greater increase than vegans in response to supplements, not that eating meat causes increases levels.

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 09, 2013
at 03:20 AM

Maybe it's an issue of dose. I don't have the full text of your paper, but it seems like the studies demonstrating increased TMAO use large amounts of red meat. If it's is anything like supplemental choline, which this animal study (http://www.ncbi.nlm.nih.gov/pubmed/2723829) noted slightly increased TMA and TMAO excretion at doses of choline smaller than 7 mmol/kg body wt, but dramatically increased TMAO at 15 mmol/kg bw, Matt may be on to something with his edit about absorption playing a role.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 11:18 AM

@Mscott, now that you mention it, they didn't vary the dose of carnitine... hmm...

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 11:25 PM

Sorry not "it" there are some that seem to be very potent and some that aren't. Still offering to e-mail anybody that paper. :)

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 10:46 PM

The first study I posted demonstrated that meat doesn't increase TMAO levels but fish, carnitine supplements, and choline supplements did. And this new paper always used carnitine supplements, any time they eat meat they also took supplements, and indeed the omnivores had higher levels because of their gut microbes, but nowhere in the study do they demonstrate that meat by itself an increase it. Correct me if I'm wrong but Figure 1A appears to show an omnivore with a baseline of 0 TMAO until he takes the carnitine. Then there's 2A which appears to show TMAO being slightly higher...

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 03:48 AM

thanks Matt. I think the mechanism is that bacteria in the fish convert carnitine and choline, you'll both have to read the 1999 paper I guess.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:35 AM

They've stuck heavy hydrogens onto the trimethylamine portion of carnitine, so when it's metabolized, they end up with heavy trimethylamine (oxide).

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 09, 2013
at 12:11 AM

Nice stabbing Stabby, I was hoping you'd comment. BTW This study suggests red meat may increase TMAO (http://www.ncbi.nlm.nih.gov/pubmed/17022649) as determined by an H1 NMR of urine at least.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:36 AM

I'm not sure the mechanism of why fish produces so much TMA, what precursor is present... dunno.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 02:58 AM

...more than other foods. And that paper definitely shows that supplements and fish have a large effect, why wouldn't red meat then? You can see how I thought that 2A must have been due to the supplement then.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 02:27 AM

Stabby, I'm not surprised that plasma levels of TMAO (Figure 2C) are similar in both groups (its a waste product, and eliminated via urine, I wouldn't expect it to be too high in even the meat eaters). Just look at 2A. The TMAO rise is only due to the steak, the d3-TMAO rise is only due to the isotopically labeled carnitine administered.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 11, 2013
at 01:01 AM

So meat increases TMAO but it's not uniquely elevating http://www.westonaprice.org/blogs/cmasterjohn/2013/04/10/does-carnitine-from-red-meat-contribute-to-heart-disease-through-intestinal-bacterial-metabolism-to-tmao/ And difference between vegetarians and omnivores at baseline probably have to do with other factors http://perfecthealthdiet.com/2013/04/lessons-from-the-latest-red-meat-scare/ Regarding whether or not vegetarians will produce less TMAO from carnitine, I think that they probably do to some extent, though Chris cast doubt on the idea. And it's kind of a moot point.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 09, 2013
at 11:24 PM

Oh ok, cool. Well according to the first paper it has quite a bit of it, and the evidence that those fish are harmful is downright scant. It would be interesting to see this new group compare TMAO increases between red meat and some kinds of fish to see which is more potent.

7a6529ea25b655132fe58d793f95547a

(2030)

on April 13, 2013
at 09:39 PM

Great review, thanks Stabby. So basically scale back on the meat, fish, veggies, dairy, grains, and......wait...oh shit.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 13, 2013
at 10:37 PM

Eating food will end you. :)

12
A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 08, 2013
at 02:08 AM

I find this all a bit at odds with the blinded RCT's on the benefits of carnitine on heart disease:

A randomised, double-blind, placebo-controlled trial of L-carnitine in suspected acute myocardial infarction

"Angina pectoris (17.6 vs 36.0%), New York Heart Association class III and IV heart failure plus left ventricular enlargement (23.4 vs 36.0%) and total arrhythmias (13.7 vs 28.0%) were significantly less in the carnitine group compared to placebo. Total cardiac events including cardiac deaths and nonfatal infarction were 15.6% in the carnitine group vs 26.0% in the placebo group"

Three-year survival of patients with heart failure caused by dilated cardiomyopathy and L-carnitine administration

"There were 6 deaths in the placebo group and 1 death in the L-carnitine group. Survival analysis with the Kaplan-Meier method showed that patients' survival was statistically significant (P <.04) in favor of the L-carnitine group. L-carnitine appears to possess considerable potential for the long-term treatment of patients with heart failure attributable to dilated cardiomyopathy"

Controlled study on L-carnitine therapeutic efficacy in post-infarction

"L-carnitine was randomly administered to 81 patients at an oral dose of g 4/die for 12 months, in addition to the pharmacological treatment generally used. For the whole period of 12 months, these patients showed, in comparison with the controls, an improvement in heart rate (p < 0.005), systolic arterial pressure (p < 0.005) and diastolic arterial pressure (NS); a decrease of anginal attacks (p < 0.005), of rhythm disorders (NS) and of clinical signs of impaired myocardial contractility (NS), and a clear improvement in the lipid pattern (p < 0.005). The above changes were accompanied by a lower mortality in the treated group (1.2%, p < 0.005), while in the control group there was a mortality of 12.5%"

The TMNO theory is an interesting idea which I hope to look into further, but as of now I find the mechanism not well supported by controlled trials.

EDIT #2

(Just some stuff I wanted to add)

Higher TMAO is associated with greater heart disease, OK. What about CRP, plasma glucose, insulin sensitivity, HbA1c, TNF-a, oxidized LDL, IL-6, and adiponectin? Surely these have been shown to affect heart disease risk. Well, carnitine supplementation has been shown to improve all of these in some clinical trials (4,5,6,7,8).

Since an ApoE (-/-) model was used to say carnitine may promote atherosclerosis, how about we look at this paper, which found that the type of CLA found richly in grass fed animal fat slowed atherosclerosis progression in ApoE (-/-) mice. There are a lot of things in meat which can exert different effects, both in isolation and in combination which should probably be accounted for. But really, how reliable are these animal models? I'm sure they are to some degree, but this study, for example, found very different effects of saturated fat, monounsaturated fat, polyunsaturated fat, and carbohydrates on atherosclerosis progression and blood lipids depending on whether an ApoE knockout or LDL receptor knockout mice were used.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 08, 2013
at 09:21 PM

Nice. I just posted my take on it too.

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 05:02 PM

There is possibly difference in administering L-carnitine in isolation vs. administering it in the presence of cofactors in the meat.

70c75942b975919dfbed8dddbd767b60

(289)

on April 09, 2013
at 04:19 PM

+1 I think this may be yet another case of misplacing the blame. When your metabolism is damaged as with SAD, many good things may appear to harm you. But removing them may do more or different kinds of harm.

11
32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 07, 2013
at 11:30 PM

Edited my reply as I read the study more and cleaned up my stream of consciousness analysis...

Most definitely red meat is getting scapegoated in popular news stories about this study. But an interesting study, nonetheless! There are flaws and some assumptions the authors have made that I don't think are quite valid.

TMAO makes sense as an oxidative stressor in the body, no surprise really that it would promote atherosclerosis. No issue with that idea. Though they do have to use knockout mice to induce atherosclerosis and much higher TMAO concentrations are necessary than what is shown in humans.

Plasma levels of carnitine and TMAO are doing some interesting things. Plasma carnitine rises first and then only after it returns to baseline does plasma TMAO begin to rise (see Figure 1e in the study). What does this mean? Who knows! I'd wager through that carnitine is absorbed early in the gut, and TMA is generated by bacteria late in the gut.

Why do antibiotic-treated guts not absorb carnitine as well? The middle graph in Figure 1e suggests this. Odd!

Why to vegans produce no TMAO? The authors claim it's the absence of the particular microbes that suggest this, and that may be the case. However, if you delve into the supporting information (freely available, by the way!), you'll notice that vegans spike carnitine more than omnivores (Supplementary Figure 6). The authors suggest this due to competitive metabolism of carnitine by gut microbes, however enhanced absorption by challenged guts (vegans) also could explain this. They lack a control experiment where antibiotic-treated omnivores exhibit the same serum carnitine response curves than do to better support their arguement.

Perhaps the vegans simply are so deficient in carnitine that they essentially absorb it all before the gut microbes have a chance to? Let's see saturation dose of carnitine, something along the lines of 2+ grams which I've seen mentioned as the maximum useful dose.

I don't doubt the possibility that vegans likely have very different gut microbes than do omnivores.

I think it's quite likely that lower carnitine levels in vegans can explain some of the results in this paper. Lower serum carnitine doesn't sound ideal to me really either.

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 08:19 PM

@Matt That's an abstract and the full text is behind the paywall for me...

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 07:54 PM

@Lumifer, malamute posted it below, here it is again: http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.3145.html

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 06:38 PM

Matt, do you have a link to the pape text? I'm rather distrustful of the press retellings of studies...

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 07:10 PM

What constitutes "aberrant gut flora"?

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 09:43 PM

Email the authors, you might get a copy. That, or find your local library or university with a subscription.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:38 AM

And they protonate the N-oxide! Not going to happen at physiological pH! Argh!

9
F5a0ddffcf9ef5beca864050f090a790

(15515)

on April 08, 2013
at 06:00 AM

I believe we underestimate the role our gut bacteria plays in our health. I also think that we need more vegetables in our diets, just like we need more tubers.

I remember listening to Daphne Miller. She said, "Use meat as spice." This made sense to me. Hunters would not catch a buffalo every single day. And even when they caught it, one buffalo would be divided among so many people - so they would end up eating ... not so much. They would diversify and mix their protein sources - raw eggs, fish, seafood, fermented/sprouted grains, local/wild greens.

I think growing your vegetable garden is one of many essential things you can do for your health.

It is not about just carnitine. It is about eating species specific diet.

I wonder if they had the same results if they fed those people RAW meat.

Medium avatar

(10611)

on April 08, 2013
at 01:46 PM

Read The Oregon Trail if you get a chance. In the Northern Plains there was fresh buffalo nearly every day for the hunting season, possibly as long as 4-6 months. The rest of the year was dried meat.

618fc5298c4a96b817c4918c795a875f

(1217)

on April 08, 2013
at 05:24 PM

yes to the vegetable garden! Growing your own food is a great way to integrate with your diet on an intimate level, even if all you have the time to grow is herbs. It is also a pretty good money saver - I never buy arugula or lettuces, because at this point the grow wild in my garden

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 05:00 PM

We don't know what the atherosclerosis profile was for plains tribes.

508a4ebd259022f415326f7a6baec00c

(482)

on April 08, 2013
at 06:36 AM

Two thumbs up!!

F5a0ddffcf9ef5beca864050f090a790

(15515)

on April 09, 2013
at 06:10 PM

@Matt - LOL at real meat.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 12:05 PM

Why would raw meat make a difference? Heck, I'm just pleased that the study used real meat as opposed to just a supplement.

7
7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 08, 2013
at 04:14 PM

Pretty interesting.

In the first paper (Wang 2011, Nature), they do exactly what you'd want them to do. They screen plasma for unknown metabolites that correlate with cardiovascular disease. I suppose there wasn't necessarily a second step if they didn't find anything. However, they found three metabolites, that along with some nifty work in mice, presented this model...

  1. Dietary phosphatidylcholine eventually converted to TMA by gut microbes
  2. TMA converted to TMAO by liver (FMO3)
  3. Increased TMAO > upregulation of scavenger receptors > choline induced atherosclerosis

This focuses on phosphatidylcholine, present in eggs, milk, liver, red meat, poultry, shellfish, and fish. Interestingly referenced (Martin, 2008, MBS) is a paper showing administration of the probiotic L. paracasei to mice with humanized micro biome resulted in decreased TMA (but not TMAO).

The second paper (Bennett, 2013, Cell Metabolism) is a little drier, and further implicates FMO3 as the main culprit in the conversion of TMA > TMAO. Suggests looking for variants that you can plug into 23andme.

The third paper (Koeth, 2013, Nature Medicine) has the big payoff...red meat. It moves from choline to another trimethylamine, L-carnitine, which is abundant in red meat. It is noteworthy that carnitine did not make the initial cut that led to the choline association with increased atherosclerosis and CVD.

I find it hard to believe they got a > 5 year vegan (self-reported) to eat a steak, but I have no doubt that diet can modulate intestinal microbiota.

So there are correlations between plasma carnitine levels and CVD risk, but they are knocked down some after adjusting for traditional risk factors.

Bottom Line:

Pretty good stuff. Offers part of an explanation for relationship between animal consumption and increased CVD risk that's not predicated on saturated fat and cholesterol. It's part of the puzzle. If I understand correctly, you'd still need the initial event (oxidized LDL penetrating the endothelial wall) and it presumably doesn't change other variables, such as the benefit of high HDL.

I think if you wanted to be a defender, you'd go to the old standby, and call yourselves a different class, so that;

  1. Maybe your gut is different from an SAD omnivore? If dietary carnitine (choline) can alter your intestinal microbiota, I would certainly expect that fast-food and sugar could, as well.

  2. Maybe you're different. If you actually have less oxidized LDL and higher HDL, maybe you are mitigating the effects of TMAO enhanced atherosclerosis?

Take Home;

  1. If you eat massive amounts of red meat, or animals in general, maybe you want to reconsider.

  2. If you supplement aggressively with L-carnitine or choline (or other trimethylamines?) you probably want to reconsider.

  3. Put this on the list with all of the other risk factors, and continue to follow along.

(Pretty funny how the choline paper generated no media buzz, but the carnitine/red meat has everybody freaking out).

E4069040201c3591b9b774df6ed9cad4

(80)

on April 09, 2013
at 05:02 PM

As you're probably aware, "the benefit of high HDL" is under serious questioning in the cardiology research community, as is the entire cholesterol hypothesis.

7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 10, 2013
at 03:29 PM

Not aware. I just follow it casually.

7
96bf58d8c6bd492dc5b8ae46203fe247

(37227)

on April 07, 2013
at 11:23 PM

I saw this earlier today and I'll be interested in the discussion here.

Until then, I'll just say it's probably the same as everything else--despite the flat pronouncements so loved by writers of articles, your results may vary. The valid point I do accept from this and similar articles is that today's CAFO beef is not your father's beef and certainly not your grandfather's beef.

I've always confounded the medical profession because despite being overweight much of my life I've been healthy other than mild complaints that proved to be sensitivity to wheat.

While on SAD, tests for inflammation were completely negative which my doctor said she never saw. Also on SAD I had perfectly normal cholesterol with high HDL.

After a year on paleo, which included lots of CAFO beef with fat and bone broths, I had cholesterol of 160, normal blood pressure and a great blood panel. So here I am at 66, not taking any meds at all and much stronger than any of my female friends.

Will you have similar results? Maybe, maybe not. Is supermarket beef ideal, or even preferred? No.

I shouldn't claim everyone will thrive on paleo just because I appear to, and problems experienced by some people from red meat don't mean no one should eat it.

There simply isn't one correct diet, no matter how many times people try to define one. And there are few if any foods that will make every human sick.

Medium avatar

(10611)

on April 08, 2013
at 12:18 PM

The "if you just had one food" questions here still puzzle me. This article points out potential flaws in making that one food red meat. We're omnivores so that we can slant our diet to what's available at any time. TMAO aside, a lot of red meat constipates me.

96bf58d8c6bd492dc5b8ae46203fe247

(37227)

on April 08, 2013
at 03:11 PM

Exactly, thhq. As much as I love beef, I wouldn't make it 3 days trying to eat it and nothing else. I think those are very silly conversations. Besides, if I could have only one food I'd choose potatoes, preferably in chip form!

6
508a4ebd259022f415326f7a6baec00c

(482)

on April 08, 2013
at 12:26 AM

  • "In fact, these scientists suspected that saturated fat and cholesterol made only a minor contribution to the increased amount of heart disease seen" -- Slipped in, but is some good news.

  • "Meat contains protein, for example, and B vitamins, which are both essential for health. But the study???s findings indicated that the often-noticed association between red meat consumption and heart disease risk might be related to more than just the saturated fat and cholesterol in red meats like beef and pork" -- Another confirmation of what many of us believe

This research seeks to find what variables can lead to heart issues, other than the myth of saturated fats and cholesterol. That's refreshing.

It would be foolish to completely deny that eating a ton of red meat, in an unbalanced way, can lead to heart health issues. Make that meat processed, and you compound the problem.

  • "That led to the steak-eating study. It turned out that within a couple of hours of a regular meat-eater having a steak, TMAO levels in the blood soared.
    "But the outcome was quite different when a vegan ate a steak. Researchers had hypothesized that vegans would not have as many of the gut bacteria needed to make TMAO, and indeed virtually no TMAO appeared in the vegan???s blood after he consumed a steak."

I will take this final point to mean that eating too much, out of balance with your other nutrients, can lead to heart problems. Eating a healthy diet, that works for you, can include red meat. Overdo it, and you're asking for complications.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 03:19 PM

I wouldn't even call it a speed limit sign, it's making conclusions with very isolated simplified systems, nature is never that simple.

Medium avatar

(10611)

on April 08, 2013
at 12:22 PM

I didn't see this article as a blanket endorsement of veganism. Just another turn in the road, and this is a speed limit sign

Bf57bcbdc19d4f1728599053acd020ab

(5043)

on April 09, 2013
at 07:44 AM

Plus one for the good news aspect.

19acef0aed67ef8dc1118d8e74edb349

(2954)

on April 08, 2013
at 05:01 AM

Inuit must have been dropping like flies.

5
70c75942b975919dfbed8dddbd767b60

(289)

on April 08, 2013
at 04:31 PM

This sounds like yet another attempt (if not by the researchers, then by the media) to establish causes via correlation.

The gist seems to be this (I only read the abstract because I didn't want to buy the full text):

  1. We find more TMAO in habitual meat-eaters after they eat foods high in L-carnitine.
  2. Having both high L-carnitine and high TMAO is associated with adverse cardiac events.

I think the form of this will look familiar to the cholesterol fallacy:

  1. We find more circulating cholesterol and fatty acids after people eat fatty foods.
  2. Higher circulating cholesterol is associated with adverse cardiac events (and is especially damning because we find it in plaques!).

Um, maybe something else is causing both the high carnitine/TMAO levels and the cardiac events? Maybe? Shouldn't we then try to get to the root and stop hacking at the leaves? Because maybe hacking at the leaves will cause other problems? We only have to consider what statin drugs and artificially low cholesterol are doing to people. I predict a similar thing will happen when people try to take this study as a suggestion to do something stupid like take antibiotics.

Also, did anyone notice the functions of carnitine in humans (see Wikipedia)? Apparently it builds bone and is a "substantial" antioxidant. Your body can synthesize it.

This statement from the NY Times article should give anyone pause:

It is quickly converted by the liver into yet another little-studied chemical called TMAO that gets into the blood and increases the risk of heart disease.

Huh? TMAO is little-studied, and yet scientist know it increases the risk of heart disease? The "increases risk" phrase was entirely unqualified, so readers will take it to mean it's established fact. I personally am unable to find studies on TMAO itself apart from L-carnitine. I consider the statement a leap and a reading-comprehension problem on the NY Times writer's part.

Some Wikipedia editor also made the same gaffe on the carnitine page:

When intestinal bacteria were exposed to carnitine from food, they produced a waste product, Trimethylamine N-oxide (TMAO), that is known to cause atherosclerosis.

Other reasons to avoid jumping to conclusions have already been mentioned by the other answerers, such as, "was this CAFO red meat?"

The abstract used a strange statement:

than did vegans or vegetarians following ingestion of l-carnitine through a microbiota-dependent mechanism

What does "microbiota-dependent mechanism" mean in terms of ingestion?

How exactly did these vegans/vegetarians ingest the l-carnitine? Did they eat red meat or take some extracted form? Did even the omnivores ingest red meat? I suspect the full article would probably elaborate on this.

EDIT

Scientists (and more so the media) really need to be a little more cautious about experimental results. Science is always discovering new things that turn the old accepted dogma upside down (it's especially bad if the old dogma itself was based on a leap of logic). Even worse is when there is actually evidence of confounding factors. For example, researchers should ask, are the people we are testing representative of the entire US population, or the average human anywhere in the world? Are there characteristics of the red meat we are testing with that might not be representative of the variety of red meat in the US, or in the world? Experimental research is not easy, and you have to be somewhat of a philosopher to do it well. Philosophy deals with abstract principles of specificity and generality - Are my results specific to a certain set of conditions? How far can I reasonably generalize this?

Medium avatar

(10611)

on April 08, 2013
at 07:38 PM

It sounded to me like they had steaks for breakfast. I wouldn't be getting out the pitchforks and gasoline when the lead research scientist is a steak-eater.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 09:48 PM

Not quite. TMAO is known to contribute CVD, it's not a guess. We have mouse models that support that. TMAO also correlates with high CVD rates in humans. That of course says nothing about the source of TMAO!

70c75942b975919dfbed8dddbd767b60

(289)

on April 09, 2013
at 03:49 PM

@Matt well, I think cholesterol can be shown to contribute to arterial plaques too. Lower the cholesterol and incidence of plaque will decrease too. I'm not saying TMAO isn't harmful, I'm saying we don't know enough yet, and we should have a bit of caution before deciding to make life changes based on this - this research is really in its infancy at this point. Fools rush in.

70c75942b975919dfbed8dddbd767b60

(289)

on April 09, 2013
at 03:35 PM

@thhq Even a researcher who has zero vested interest may still make a procedural error. There's a difference between criticizing for dishonesty/conflict-of-interest and criticizing for technical mistakes. Not that I'm saying their guilty of the latter either; I don't have enough info, which is why I kept it as an open question.

5
10121ac7b6beb99c0fbfbf1522c50adb

on April 07, 2013
at 11:33 PM

I'm always open to new studies with the potential of changing the way we paleo, health-conscious Homo sapiens eat???if they actually apply to how paleo people eat.

The study was conducted using a single cut of meat. Are beef hearts the same as tongues as sweetbreads? And the meat used was extremely unlikely to be grass-fed and finished. And then compare that to a single v*gan. N=1 is nice and all when the results are used to help that original 1, but the authors of the study are using that 1 v*gan to demonstrate the optimal levels of health for every.single.person.

Sure, that annoys me and all, but the part I can't read without leaving a furious comment is the part on antibiotics. I'm paraphrasing here, but I'm pretty sure the article said something like this: let's give every person with a heart and therefore potential of heart disease antibiotics so we can 1) destroy every last bacterium in people's guts so they can't properly digest anything and 2) assist in the evolution of new, antibiotic-resistant strains of bacteria that might have greater human-killing superpowers. Delightful, no?

I type this while chowing down on ribs.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 03:20 PM

It was conducted with isotopically labeled carnitine as much as anything. As Lumifer pointed out, it is an effect due only to carnitine.

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 07:48 PM

@Leah Chemistry is a science :-) The same chemicals (e.g. carnitine) from Soylent would the the same as the same chemicals from acorn-fed bacon. However Soylent would have different chemicals (=nutrients) in different proportions compared to that acorn-fed bacon.

800e726cb5dff569fd8edf604c3e2793

(1655)

on April 08, 2013
at 03:04 PM

The article explicitly identified *carnitine* as the problem. So no, the cut of the meat doesn't matter.

508a4ebd259022f415326f7a6baec00c

(482)

on April 08, 2013
at 05:36 AM

Good point on different cuts. Good point on the quality of the meat and where it came from. I would assume it came from a factory farm.

10121ac7b6beb99c0fbfbf1522c50adb

(1193)

on April 08, 2013
at 07:27 PM

I see what you're saying, but by that logic, nutrients from Soylent would be the same as nutrients from a high quality strip of bacon with regards to the body's response. If that's what you're implying, I respect that.

4
Medium avatar

(110)

on April 10, 2013
at 11:20 PM

Christ Masterjohn's analysis http://www.westonaprice.org/blogs/cmasterjohn/2013/04/10/does-carnitine-from-red-meat-contribute-to-heart-disease-through-intestinal-bacterial-metabolism-to-tmao/

"The biological effects of a food cannot possibly be reduced to one of the biological effects of one of the food???s components."

E4069040201c3591b9b774df6ed9cad4

(80)

on April 11, 2013
at 11:47 PM

I find that statement puzzling, inasmuch as his organization - Weston A. Price Foundation - advises not drinking fluoridated water. On what evidence basis does Masterjohn propose that individual, isolatable components of food cannot - categorically - be agents of disease or health? With fructose, we know that to be false. It is also plausible that carnitine -> TMAO also be an agent of disease.

4
7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 10, 2013
at 06:00 PM

Mark Sisson weighs in: http://www.marksdailyapple.com/does-red-meat-clog-your-arteries-after-all/#axzz2Q4CYLRW8

We should definitely keep an eye on this and any other future research. I???m particularly interested in what this means for research into the effects of gut flora on human health.

Balanced response, as expected.

Reports aren't always what they seem, but just because studies have been "debunked" in the past doesn't mean you rush out and try to "debunk" every study in which you don't like the conclusion (especially if it's not your day job).

4
B6fb8f55070f5390bd87a03b025f5bde

(60)

on April 08, 2013
at 03:46 PM

0

This is indeed troubling. Everyone on paleo eats red meat and therefore consumes large amounts of carnitine. Some eating paleo also supplement with carnitine or acetyl l carnitine to increase energy or enhance brain function. Now this study which seems to be very straight forward in the negative effect TMAO exerts on plaque and heart disease. Surely we need more studies but if further studies indicate the same, paleos must be willing to question whether they are primarily paleo because it's "natural" or they are paleo because it is healthy (and enhances life span and risk of heart disease). If they answer that they are paleo because it optimizes life span (and the study is believed and replicated), paleos should abandon the consumption of red meat.

Btw, anyone who posts that this study is about optimized gut flora or that eating fruits and vegetables or cultured foods or probiotics will somehow prevent TMAO's effect on heart plaque has not read the study. Interestingly (but without all the mainstream press) Nature published a paper demonstrating that choline also promotes TMAO increasing heart disease: http://www.ncbi.nlm.nih.gov/pubmed/21475195 This study may also be relevant as us Paleos consume large amount of eggs and fish which are loaded with choline (and some of us supplement with choline, phosphatidylcholine or phosphatidylserine). Again choline (and derivatives) definitely promote brain function but possibly at the cost of future heart disease.

Ebb10603524dd22621c1155dd7ddf106

(19150)

on April 08, 2013
at 04:15 PM

I'm not suggesting that. You were suggesting that others who talked about gut flora were suggesting that, and I attempting to clarify what they likely meant. :-)

Ebb10603524dd22621c1155dd7ddf106

(19150)

on April 08, 2013
at 04:49 PM

LOL, no. Even if red meat is shown to directly increase TMAO and atherosclerosis, it would still be a different and unique kind of evil, separate from the many evils of soy. Although, funny enough, soy contributes to this discussion too, as it's the most common source of lecithin in SAD after meat.

B6fb8f55070f5390bd87a03b025f5bde

(60)

on April 08, 2013
at 04:06 PM

I understand that you're suggesting that optimizing your gut flora (by eating more veggies, fruits, cultured foods, or supplementing with probiotics) will "produce less (or none) of TMAO" but there's no evidence of that. What there is evidence of is that red meat has a peculiar effect in the creation of a particular kind of bacteria in the human gut which (through TMAO) leads to heart disease. Exogenous choline consumption does create TMAO and leads to heart disease, at least in mice, and likely in humans: http://www.ncbi.nlm.nih.gov/pubmed/21475195

E4069040201c3591b9b774df6ed9cad4

(80)

on April 08, 2013
at 09:15 PM

Even worse than the atherosclerosis...will be the triumphant smugness of the vegans.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 08, 2013
at 09:46 PM

LOL, a single study and you've found the new villian? TMAO via carnitine? Oh brother.

Ebb10603524dd22621c1155dd7ddf106

(19150)

on April 08, 2013
at 03:53 PM

*anyone who posts that this study is about optimized gut flora...will somehow prevent TMAO's effect on heart plaque has not read the study* First, I think anyone who states that is implying that optimized gut flora will produce less (or none) of TMAO, not that TMAO does or doesn't do what the latest study claims. Finally, the metabolites of carnitine are choline, TMAO, and betaine (per the study). Saying choline creates TMAO does not seem to be correct.

B6fb8f55070f5390bd87a03b025f5bde

(60)

on April 08, 2013
at 04:23 PM

So we're agreed: red meat is the new soy.

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 10, 2013
at 10:14 PM

Hey Kali, if you wouldn't mind I'd like to see any papers you have on protein restriction extending life span.

2e6e673ce3eb647407d260d4d57a731b

(1021)

on April 11, 2013
at 06:51 PM

"choline (and derivatives) definitely promote brain function but possibly at the cost of future heart disease." assuming you mean choline helps the brain develop and function more properly possibly at the expense of heart health, well there's nothing wrong with that. quality over quantity.

B6fb8f55070f5390bd87a03b025f5bde

(60)

on April 08, 2013
at 03:57 PM

Interestingly this study provides yet more evidence against the long debunked lipid hypothesis and saturated fat being the cause of heart disease. However red meat may be out as an optimized protein source. While we're on it, it's mostly protein restriction (intermittent or otherwise) that is largely responsible for life extension and autophagy (numerous citations available upon request). High protein is not healthy, though it may be sexy by optimizing muscle mass. High fat, low carb, adequate protein is optimal.

4
E4069040201c3591b9b774df6ed9cad4

on April 08, 2013
at 05:19 AM

Before spleens are vented and teeth gnashed, perhaps it's best for everyone to read one of the studies referenced in the article:

"Intestinal microbiota metabolism of l-carnitine, a nutrient in red meat, promotes atherosclerosis" Koeth, Wang, et al. Nature Medicine(2013), doi:10.1038/nm.3145

http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.3145.html

n=2595 in this study. Not definitive, by any means. Certainly a sufficient starting point for investigation of TMAO production from consumption of CAFO vs. grass-fed meats.

Also, need it be said: atherosclerosis is probably polygenic.

3
57a9566896759c703991afa106c4fe4f

(56)

on April 11, 2013
at 05:26 PM

The best response i've seen to the new red meat study is this article by chris masterjohn. IMO, he thoroughly debunks the study.

2
7958f0332853bacdc54c38423f2383a6

on April 07, 2013
at 11:39 PM

I really want to know if grass fed beef causes a different reaction, and if having enough K-2 in your diet (ahem, thanks grass fed beef fat!) is protective even if the gut flora in grass-fed-meat-eaters has the same response. I would expect the gut flora in people eating paleo, or even just no grains/refined sugar, would be very different from that (those?) in people eating a conventional diet.

32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 09, 2013
at 03:04 AM

Carnitine is carnitine, grass-fed or not. The same response occurs with or without meat.

96440612cf0fcf366bf5ad8f776fca84

(19413)

on April 11, 2013
at 02:02 PM

Yes Matt, but there may be other factors in grassfed meat absent from CAFO, and vice versa. I certainly wouldn't expect cattle confined to live in their own waste and fed expired candy with wrappers, and other inappropriate feed to be as beneficial to humans as those free to roam, consume forage, and be exposed to sunlight. Would you? Just looking at the livers of CAFO chicken versus pastured chicken tells you a whole lot.

1
32f5749fa6cf7adbeb0b0b031ba82b46

(41757)

on April 10, 2013
at 02:47 PM

Chris Kresser weighs in: http://chriskresser.com/red-meat-and-tmao-its-the-gut-not-the-meat

No surprise he's a skeptic of the study. Makes the claim that healthy user bias means you have better gut flora than the average. Suggests that the omnivores in the paper suffer from dysbiosis and SIBO and that explains why their guts produce trimethylamine when fed red meat.

(Community Wiki'd this, others can edit to add more of his argument if you like.)

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 10, 2013
at 05:12 PM

But maybe just not more than the beneficial nutrients in meat (like carnitine!) reduce the risk.

7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 10, 2013
at 04:07 PM

Also, to be fair to the authors, they aren't saying that red meat causes heart disease, just that it increases the risk through the described mechanism in the mice, and the biomarker, TMAO, corresponds to increased risk in the patients that were sampled. I believe one of the authors remarked that steak is too tasty to give up, but that he might cut back a little. The researchers/Kresser are more on the same page than not.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 10, 2013
at 05:09 PM

Good catch, that part bugged me. The better argument would be that if you look at the epidemiology on red meat, it's only the processed red meat that's associated with heart disease risk, and vegetarians don't consume processed meat, so it would be more likely that this (amongst other things like the healthy user effect) explains the lower rates. Though Chris doesn't believe that processed meat is bad so I guess that prevents that. Fried bacon has the most reactive HCAs of any meat I've seen (though following this reasoning harsh cooking methods used on fresh meat would also raise risk...)

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 10, 2013
at 04:12 PM

Jim B, yeah I noticed that about the epidemiology he cited, like the Epic-Oxford study, which did find decreased CVD in vegetarians. He switches from saying vegetarians don't have less heart disease to vegetarians don't have lower mortality.

7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 10, 2013
at 04:04 PM

1. "The Epidemiological Evidence is Inconsistent" - doesn't support Kresser, either. 2. "What's in the Gut?" (whoop) - I said the same thing in this thread before Kresser - PH loves me and showers me in adulation. Anyway, mostly nice work by Chris, but disingenuous to imply there should be "gut controls". They are definitely needed, but gut characterization has just really started in earnest. Patience everybody, we'll get there.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 10, 2013
at 05:11 PM

But maybe just not more than the beneficial nutrients in meat (like carnitine!) reduce the risk. Damn epidemiology...so speculative and given so much importance.

Be1dbd31e4a3fccd4394494aa5db256d

(17969)

on April 10, 2013
at 05:13 PM

But maybe just not more than the beneficial nutrients in meat (like carnitine!) reduce the risk. Though the best policy might be to eat red meat but cook it carefully to get the best of both worlds. It's funny, the study that the authors of this new paper post to prove that red meat causes heart disease contradicts their thesis.

A2c38be4c54c91a15071f82f14cac0b3

(12682)

on April 10, 2013
at 04:13 PM

Jim B, yeah I noticed that about the epidemiology he cited, like the Epic-Oxford study, which did find decreased CVD in vegetarians. He switches from saying vegetarianism isn't associated with less heart disease to vegetarianism isn't associated with lower mortality.

1
7e6644836cdbcbe2b06307ff7db92d31

(693)

on April 09, 2013
at 03:04 PM

  1. Would have thought this would get a little more play? What is this site about?

  2. I really appreciate how people "review" these studies - not summarize or give their impressions, but critically review - I am indebted to all who undertake this endeavor simply for the entertainment it provides. You should e-mail the authors to point out the flaws. Why not, right?

1
Fb67dc30cead043d1d13ea503a3044dc

(3280)

on April 09, 2013
at 06:46 AM

I found this brief write up, linked by Anastasia at PrimalMedEd:

http://examine.com/blog/media-sensationalism:-meat-is-bad-for-your-heart/

Tl;dr:

"The study found that in genetically modified mice, a high (but not impossible) dosage of l-carnitine did double plaque buildup. This may or may not be related to TMAO, we cannot say. This may or may not happen in humans, we cannot say. Overall? It's just preliminary research that should only interest other researchers, not the layperson."

Still, I'm going to keep an eye on this one.

96440612cf0fcf366bf5ad8f776fca84

(19413)

on April 11, 2013
at 02:02 PM

But humans aren't genetically modified, and humans aren't mice. These are merely models that might or might not shed light on some mechanism, which might be valid in those specific types of mice, but not the general population of humans. Case in point: mice can eat raw grains - we cannot.

Fb67dc30cead043d1d13ea503a3044dc

(3280)

on April 12, 2013
at 04:57 AM

Yes, exactly. I pointed that quote out specifically because it mentions GMO mice, which we aren't -- I wasn't clear. I was thinking, Ok, but what do these mice have to do with humans?...but that I was still going to watch for further studies.

0
2e6e673ce3eb647407d260d4d57a731b

(1021)

on April 10, 2013
at 06:58 PM

a more pertinent question would be why does anyone give a damn about any of this?

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