3

votes

What are your thoughts on Fructose Malabsorption/Intolerance?

Answered on August 19, 2014
Created August 15, 2010 at 5:14 PM

http://www.foodintol.com/sugar.asp

My N=1 30 day fructose elimination showed me that fructose and I do not agree.

This may be the next wheat...we already know how bad fructose is by itself... Are the small amounts in fruit ok for most similarly to how most tolerate wheat before they take 30 days and clear their system

Have you done a self 30 day trial?

Thoughts?

Cc69a51b427eaad36251cce9dcca4d3a

(1074)

on April 10, 2013
at 09:28 AM

forget the veggies, just add white rice and white potato/tubers. meats/fats + pure glucose source = optimal

Medium avatar

(39821)

on August 30, 2011
at 05:41 PM

Domer: Not even close to correct. Aside from being 22.2% more fructose, the glycosidic bond between glucose and fructose in sucrose makes absorption occur at much different pace. Are you perhaps a corn refiner?

5f0158c23fcb5636e57b4ce097784da0

(1386)

on November 13, 2010
at 10:38 AM

"thefartingpear" - best domain name ever.

9d741bcbe702044635f2ce3078043054

(1435)

on November 12, 2010
at 04:52 PM

HFCS is so close to sucrose as to be nearly indistinguishable. Sucrose is 50/50 glucose and fructose. HFCS is usually 55% fructose and 45% glucose. No magic there. Fructose is not a protein, so it's true that antibodies will not go after it.

4b97e3bb2ee4a9588783f5d56d687da1

(22913)

on November 12, 2010
at 12:44 PM

It's all in my head then... I'll go buy some HFCS now.

4b97e3bb2ee4a9588783f5d56d687da1

(22913)

on August 17, 2010
at 03:02 AM

I think it was on hyperlipid, I was reading about vit C creation and the theories about why we don't create it, and other animals which don't and it's not because their eating it or not eating it. It makes me think that alot of these types of changes or adaptations are for other reasons, fructose absorption isn't required or optimal, and therefore not selected for to keep running on, but capable of liver conversion to fill fuel needs... Speculature. So much still to learn on why's and if anything we "know" is right... Augh!

4b97e3bb2ee4a9588783f5d56d687da1

(22913)

on August 16, 2010
at 05:08 PM

@JohnR: yes, that was the intention I question vegetables for the antinutrients, not any taste, I actually enjoy them, but my mission is optimal health, and with so much proven wrong so often, we should question everything

95ab15c8ef50ff0daf87ccbdd52cd3b8

(2384)

on August 16, 2010
at 03:37 PM

It is "similar to wheat" in the sense that it's everywhere and people may be sensitive to it without realizing it. I think that's what the OP meant. Re the paleo dudes' (and it is always "dudes", isn't it?) fears of veg, spot-on... yet another place where people justify juvenile food pickiness with dubious science.

4b97e3bb2ee4a9588783f5d56d687da1

(22913)

on August 16, 2010
at 11:23 AM

Digestion and headaches, a general malaise, feel like a slug. I'm usually very energetic

1f70da0b737e9c6e7679a248f4228a01

on August 16, 2010
at 08:38 AM

What was the 'proof' - digestive, mood, energy..?

62ed65f3596aa2f62fa1d58a0c09f8c3

(20807)

on August 16, 2010
at 02:37 AM

Actually, I thought it was common knowledge that many people, if they guzzle whole fruit in a short period of time, will soon get the trots. I don't get this, so I always found it amusing. I remember me and my friends really ate a ton of persimmons (the crunchy kind you can eat right off the tree), and my mother warned us to not eat so much and we all ignored her. Then we went to walk to the library, and my friends were in severe distress by the time they arrived and actually ran the last blocks to get to the bathroom faster before it was too late...

Ab6d5fded95559985919961c62b1847d

(434)

on August 15, 2010
at 09:03 PM

Fructose malabsorption is definitely a malabsorption issues as opposed to a tolerance issue. People with fructmal can tolerate fructose if it's absorbed. The problem is that the fructose isn't absorbed so it moves to the lower intestines and wreaks havoc there. I'll edit my post with a link for this info.

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14 Answers

6
2a2e49ade3160d6a2455a8f8661fc085

(60)

on August 16, 2010
at 02:59 PM

A about 2 years ago (after feeling poorly for about 18months), I was diagnosed with Fructose Malabsorption. Once I tuned my diet accordingly, by figuring out what amount of fructose I could tolerate, the change was amazing (back to feeling good, having energy again, and no mood-swings!).

As someone with FM, I can offer the following resources that I've found helpful over the years:

Also, since it has not been mentioned yet, I should also highlight that fructose and fructans (chains of fructose molecules) must be avoided. These are present in Wheat, brown rice, onions, green beans, carrots, asparagus, garlic, and some other stuff (see: http://www.thefartingpear.com/index.php/foodsearch/index/fructans).

5f0158c23fcb5636e57b4ce097784da0

(1386)

on November 13, 2010
at 10:38 AM

"thefartingpear" - best domain name ever.

5
77877f762c40637911396daa19b53094

(78467)

on August 15, 2010
at 10:39 PM

This may be the next wheat...

First off, it's not similar to wheat at all since it's an intolerance as opposed to an allergy, i.e. there is no immune response to fructose.

we already know how bad fructose is by itself... Are the small amounts in fruit ok for most similarly to how most tolerate wheat before they take 30 days and clear their system

Many studies to date showing that fructose is deleterious to health have done so with ridiculous/unrealistic doses (25% or more of diet). On top of that, a lot of them have been rodent studies. What you have for evidence is that chowing down >100g of fructose a day will cause metabolic syndrome and other nasties. This would involve eating large amounts of fruit or eating substantial quantities of garbage food like non-diet sodas. This is not useful at all.

YOU might be intolerant of fructose, but it is a total non-sequitur to make the leap to saying that fructose is bad in general, even in small amounts found in real food, without any reference to dosage or context (e.g. pwo nutrition vs. obese people on a hypercaloric diet, etc). This blaming of particular macronutrients as the just-discovered-cause-of-all-our-health-problems is sensational at best (sat fat anyone).

From a paleo standpoint, fructose is prevalent in most vegetables and fruits in varying quantities. We have specific metabolic pathways for fructose absortion (GLUT 5). It is not advantageous to evolve in a direction where we lose our ability to absorb/metabolize fructose.

There is a lot of good information out there, but there are also a lot of alarmists trying to push their own agendas. Vegan dairy bashers come to mind. Some paleo dudes seem to have a hypochondriac like fear of vegetables. Reading the actual studies themselves might be a snore but its important to follow the actual science as opposed to getting caught up with convincing looking pseudoscience or idiosyncratic reasoning.

95ab15c8ef50ff0daf87ccbdd52cd3b8

(2384)

on August 16, 2010
at 03:37 PM

It is "similar to wheat" in the sense that it's everywhere and people may be sensitive to it without realizing it. I think that's what the OP meant. Re the paleo dudes' (and it is always "dudes", isn't it?) fears of veg, spot-on... yet another place where people justify juvenile food pickiness with dubious science.

4b97e3bb2ee4a9588783f5d56d687da1

(22913)

on August 16, 2010
at 05:08 PM

@JohnR: yes, that was the intention I question vegetables for the antinutrients, not any taste, I actually enjoy them, but my mission is optimal health, and with so much proven wrong so often, we should question everything

3
0bc6cbb653cdc5e82400f6da920f11eb

(19245)

on August 15, 2010
at 11:39 PM

I would be cautious about interpreting a 30 day fructose elimination.

I do not know specific details, however many transporters like the GLUT5 that absorbs the fructose from the small intestine are regulated by the presence of the molecule they take up. What this could mean is that if you eat no fructose for a month your ability to absorb fructose could be greatly reduced. Reintroducing it could result in malabsorption and may take a day or two before you can produce new GLUT5 transporters. Thinking you have a malabsoption problem when you don't doesn't help anyone.

Also the absorption of fructose takes place near the tips of the villi of the cells of the small intestine. Any damage to the villi, such as from celiac disease or other gut disease, could reduce the ability to absorb fructose. Maybe any malabsorption problems would improve again with a healthy gut lining.

Fructose malabsoption seems like an interesting new idea and reducing fructose looks like it could be a usefull experiment if you have possible symptoms like IBS.

3
Ab6d5fded95559985919961c62b1847d

(434)

on August 15, 2010
at 07:15 PM

My digestive system has been screwed up since I was a kid, so I think I have a predisposition for food intolerances. I have a ton of them (many of which are irrelevant with this WOE, thank goodness), fructose malabsorption included. I did a fructose elimination diet a while ago and found I don't tolerate it either. After I cut out all fruit and higher fructose veggies (for a couple months), I started gradually adding fructose-containing foods back in one by one and found I was supper sensitive. I had a reaction after any sort of fruit or higher sugar vegetable (like carrots) I tried.

I think most people can tolerate the small amounts of fructose in fruit. I think after a person clears their system of it, the reaction to fructose will be more pronounced from their perspective because they've gone thirty days without it. Once you realize how good you feel without something you can't tolerate, you notice it more when that something makes you feel terrible. Though I don't know if your tolerance of it actually lessens once you rid it of your system.

ETA: I know I said "tolerance" a lot in my response but fructose malabsorption is, as the name suggests, a malabsorption issue. It's not a tolerance issue.

Fructose Malabsorption Disorder is the inability to absorb fructose and fructans. This condition is NOT characterized by the inability to "tolerate" fructose/fructans. Sufferers of Fructose Malabsorption have no difficulty tolerating fructose/fructans once they have been absorbed. However, inducing absorption is difficult or impossible for FructMal sufferers. The symptoms of the disease are the result of having unabsorbed fructose/fructans in the lower intestine.

Link.

2
62ed65f3596aa2f62fa1d58a0c09f8c3

(20807)

on August 16, 2010
at 02:32 AM

Sometimes if a population is away from a food source for a long time, and there is no natural selection towards a needed ability, then this ability can degrade or become lost. Just like fish in underground caverns eventually lose all their pigment and eyesight over the generations. Things are not conserved if they are not needed. It could be that some populations did not have access to much fructose and so their ability to process and tolerate it has degraded. However, since there is a specific metabolic pathway in the average human that is specifically set up to handle fructose, I do not think it likely that humans in generally were generally designed not to eat any at all. I do think were were designed to eat much much less than currently eat on the average SAD. And I also would not be surprised if people with all kinds of gut damage, blood sugar issues, and gut flora imbalances would have added problems with any kind of sugar or starch. However, I do think that for the big majority of humans, moderate intake of fructose such as would be obtained from moderate intake of whole fruits, if done from childhood such that metabolic damage never happened in the first place, would be perfectly fine. However, if I were native American, innuit, or one of the groups that might be less adapted to carb intake, I'd be extra careful.
-Eva

4b97e3bb2ee4a9588783f5d56d687da1

(22913)

on August 17, 2010
at 03:02 AM

I think it was on hyperlipid, I was reading about vit C creation and the theories about why we don't create it, and other animals which don't and it's not because their eating it or not eating it. It makes me think that alot of these types of changes or adaptations are for other reasons, fructose absorption isn't required or optimal, and therefore not selected for to keep running on, but capable of liver conversion to fill fuel needs... Speculature. So much still to learn on why's and if anything we "know" is right... Augh!

2
5672b2d190891342389e764cc4056ca9

(1304)

on August 16, 2010
at 12:36 AM

Large amounts of fructose are not easily digested, usually 50 gr being the maximum most people can comfortably handle.

The ratio between fructose and glucose in fruit is also important, as glucose helps with fructose absorption. If you look at the nutritional values, you can identify (and avoid) fruits that are high in fructose and low in glucose: apples, pears, melons (especially water melon) are among the worst offenders.

Other food intolerances (gluten) can cause fructose malabsorption but often, once you fix the first problem, fructose malabsorption disappears.

Final thought: are modern fruits too sweet for us to digest properly?

2
72a1e3ccf044c2fe1f994e10927e18a8

(183)

on August 15, 2010
at 07:45 PM

Seems possible if the fructose uptake mechanism in your intestine is deficient... I would say this seems rare (would be extremely evolutionary unfavorable). Just from personal experience I haven't heard many people complain of loose stool/ excessive gas from eating fruit (via increase of osmotic pressure in the intestines/ bacteria breaking down undigested fructose) If it were getting in your body since it is a simple sugar there is no enzyme which needs to break it down... only an enzyme in the liver which needs to convert it to pyruvate --> glycogen. So, like this website alludes to, I'm hesitant to believe it can be very similar to lactose intolerance. Of course I'm sure there are a handful of mutations in the aldolase which converts fructose into a glycolysis intermediate that decrease its affinity... but it seems that people who suffer from fructose problems typically do so because of a malabsorption issue. If you keep it down you should be fine (I think gluten's a lot worse)

I DO think that this is a very important step in an optimal diet. I just really love fruit... so I eat 10 blueberries and a teaspoon of honey after my workout. Its definitely not necessary and if you can live without it, more power to you. (just don't go crazy on the glucose) Raw fructose is about 1.7x sweeter than sucrose so you can eat a bit less of it for the same punch (heating catalyzes the reaction to a 6 carbon fructose sugar that is about the same as sucrose so it mitigates the advantage). I'm gonna stay with a bit of fructose / day, but if I could ever give up sugar. It would be a good day.

On the evolutionary side: We have specialized transportation systems for fructose (see Glut5 transporter), so I can't say I think it decreases our fitness too much (evolutionarily speaking... although optimal health/ your health goals may need a different analysis)

62ed65f3596aa2f62fa1d58a0c09f8c3

(20807)

on August 16, 2010
at 02:37 AM

Actually, I thought it was common knowledge that many people, if they guzzle whole fruit in a short period of time, will soon get the trots. I don't get this, so I always found it amusing. I remember me and my friends really ate a ton of persimmons (the crunchy kind you can eat right off the tree), and my mother warned us to not eat so much and we all ignored her. Then we went to walk to the library, and my friends were in severe distress by the time they arrived and actually ran the last blocks to get to the bathroom faster before it was too late...

Ab6d5fded95559985919961c62b1847d

(434)

on August 15, 2010
at 09:03 PM

Fructose malabsorption is definitely a malabsorption issues as opposed to a tolerance issue. People with fructmal can tolerate fructose if it's absorbed. The problem is that the fructose isn't absorbed so it moves to the lower intestines and wreaks havoc there. I'll edit my post with a link for this info.

1
3408e1d1c7d6b49fca2edb96b433ff9b

on March 04, 2012
at 07:32 PM

I am unable to eat most fruits as well. The only thing I allow myself is a little lime juice when I cook fish. I seem to do ok with that so far. It can be very limiting here on Paleo but possible. I just focus on meats and veggies, and I do use lactose free milk and butter. :) I have not tried to reintroduce other fruit and don't miss it. I never really liked it to start with. I do however wonder if this could be a reason I have low energy.

Cc69a51b427eaad36251cce9dcca4d3a

(1074)

on April 10, 2013
at 09:28 AM

forget the veggies, just add white rice and white potato/tubers. meats/fats + pure glucose source = optimal

1
E9214b7dfa3352f4e559555f87311287

on August 15, 2010
at 09:28 PM

Thoughts on fructose malabsorption on Evolutionary Psychiatry:

http://evolutionarypsychiatry.blogspot.com/2010/08/ibs-fructose-depression-zinc-and-women.html

0
1fa27cc9349ee2130c975a79ec8e41a1

on January 02, 2013
at 12:31 PM

fructose malabsorption is medically diagnosable with a hydrogen breath test. If youre concerned, see your doctor.

0
96bf58d8c6bd492dc5b8ae46203fe247

(37227)

on March 04, 2012
at 08:06 PM

This is a great question. I'm happy to report that even when I was very sick with (unrecognized) gluten sensitivity I was able to handle fruit just fine so the good news it doesn't happen to everyone. This site says it actually helps to eat glucose with your fructose.

I have gone 30 days or more without fruit and when I re-introduced it I felt much better. While some raw vegetables produce excess gas for me, etc., fruit does not.

I was shocked to hear the 50g per day max, though--other than my days of slugging HFCS Coke and Pepsi that's a lot. So despite all my PH defense of fruit and fructose I'm pretty much in awe of anyone who frequently eats 50g or more.

My typical daily intake (a grapefruit and a banana or handful of berries) plus about a tbsp of honey. My total sugars may approach 50g but my fructose is definitely less if you check the tables at the link I provided. Even when I get a pineapple once in a while I don't hit 50g of fructose that day thanks to portion control and skipping the other fruits.

0
79bfe9eda3a1372db236feac1db256a0

on August 30, 2011
at 05:36 PM

So, Ive been living with my Fructosemalabsorption for a year now. I pretty much know what I can eat and what to stay away from. Id like to change my whole dietto paleo diet - of course eating only veg./fruits I can. Has anyone here made experience with it? If yes did you realize a better absorption of fructose? I heard that might happen....very curious bout that. Monika

0
5f0158c23fcb5636e57b4ce097784da0

(1386)

on November 13, 2010
at 10:49 AM

fructose malabsorbtion is certainly real, and can run in the family (genetic). however, i found that the capacity to absorb fructose varies very widely depending on the health of my gut flora. for example, one could have a bacterial disbyosis or candida overgrowth in the small intestine and think that it's FMA. meaning: try to reset your colon (maybe 1-2 days fasting, eating only macadamias or so), populate it with the most effective probiotics (like L. GG ("culturelle"), boulardii, coagulans, etc) and it might very well be that you can tolerate much more F. than ever before (it might not cure the FMA, but at least it changes how the remaining F. is being metabolized afterwards in the colon)

0
72fab5260f7000f851832bab7151682e

on November 12, 2010
at 07:34 AM

Fructose malabsorption is not a food allergy, meaning there is no production of IgE antibodies or release of histamine. There is also no typical allergic symptoms, like itching or hives.

9d741bcbe702044635f2ce3078043054

(1435)

on November 12, 2010
at 04:52 PM

HFCS is so close to sucrose as to be nearly indistinguishable. Sucrose is 50/50 glucose and fructose. HFCS is usually 55% fructose and 45% glucose. No magic there. Fructose is not a protein, so it's true that antibodies will not go after it.

4b97e3bb2ee4a9588783f5d56d687da1

(22913)

on November 12, 2010
at 12:44 PM

It's all in my head then... I'll go buy some HFCS now.

Medium avatar

(39821)

on August 30, 2011
at 05:41 PM

Domer: Not even close to correct. Aside from being 22.2% more fructose, the glycosidic bond between glucose and fructose in sucrose makes absorption occur at much different pace. Are you perhaps a corn refiner?

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