Very interesting questions/posts lately concerning IF and extended fasting. I have read the books of Taubes, Wolf, Pilon and other assorted guru's blogs and have not seen a lot of data concerning extended fasting. Thanks to Paleohacker Rob Sacks for posting many links concerning extended fasting and especially his experience in healing migraines. With the season of religious fasting (for those who are into that) approaching I have been researching this topic with an intent to determine the following:
Why after about 12-15 days of good meat, fat, veggies etc, do I get intense sugar cravings that almost nothing will abate? I thought this was just a will power issue, but then this sentence from Rob Sacks sticks out to me
"It takes longer for the body to switch over to "fasting mode" than most people realize. The brain takes two weeks to fully switch over to using ketones. It's the brain's demands for glucose -- which gradually diminish as the brain switches over to ketones -- that make people feel bad when they begin fasting. People think they are "in ketosis" within a day. Actually ketosis is a matter of degree, and it takes about four weeks of continuous, complete fasting for the body to maximize its use of ketones."
Could I be "caving in" because of my body's craving for glucose due to a lack of keto-adaptation? Why don't I crave sweets at first but after about two weeks will go to a lot of trouble to obtain sugar? (And although I am female, I don't think this is a menstrual cycle issue as the timing of my cycle does not make a difference) I thought being keto adapted meant that you show ketones in your urine, you could skip a couple a meals easily (I can) and work out fasted without getting light headed (I can). I guess this is way more complex that just "pee on the strip and watch it turn purple". If this is true, then am I completely destroying the progress I have made in the prior 14 days toward becoming keto-adapted. Any thoughts?
asked bytexasleah (4111)
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on February 14, 2011
at 01:26 PM
Hi Leah. Thanks for mentioning that my earlier posts were helpful. I really appreciate it!
It takes a long time to lose carb cravings completely. In my case, over a year.
Like Eva said, ketosis and loss of carb cravings are two different things. It would seem logical that the more time you spend in ketosis, and the deeper your ketosis, the sooner your carb cravings will disappear. But this is only an assumption.
Ketosis can be extremely valuable for obese people who want to lose weight quickly. It's also useful as a treatment for neurological disease. But in general, for the average person, I'm not sure it's a good idea to remain in ketosis for a long time. Most people may be better off including starch (potatoes, sweet potatoes, taro, etc.) in their diets. Most likely, tubers were a big part of the diet for many of our paleolithic ancestors.
...am I completely destroying the progress I have made in the prior 14 days toward becoming keto-adapted.
No. It's like falling off a horse when you're learning to ride. Just climb back on. Eventually you'll get to your destination. (Luckily we don't break bones with this kind of horse!)
Everybody I know personally (including me) screwed up a lot in the beginning. A friend of mine used to avoid carbs for a couple of weeks, then lose control and go to Taco Bell and scarf down a giant cup of corn syrup and five bean burritos. She did this for two years. Despite the frequent backsliding, during those two years she managed to lose 30 pounds. When she saw that this had happened, she finally became convinced that low-carb diets work. At that point, finally, she stopped eating carbs completely and entered a state of constant ketosis. Ketosis suppresses appetite, so she no longer had much desire to eat, and she has been losing weight effortlessly and quickly ever since. It's a remarkable thing to see.
When you lose control and eat a sugary meal, I think the results are noticeable. For the next few days, carb cravings intensify. I noticed that, and everybody I've asked has said they notice it too. But then the cravings fade and you start marching forward again.
The longer you do this, the easier it gets. It really does.
on February 14, 2011
at 04:46 AM
Being in ketosis is not the same thing as being fully ketoadapted. In the first condition, it means that you have switched to a basically different energy burning state and ketones are showing in the urine. In the second condition, it means that your body has gotten most of the kinks out and the system is now running much more smoothly. For most people, the majority of adaptation happens early on and the longer you go, the better adapted. I have heard some people say that 3 months is a better time frame to look towwards for really decently settled adaptation to fat burning/ketosis modes. And I am not sure it is possible to become as well adapted as you would if you had eaten healthier since birth. I think after decades of eating sugar, the body develops around that fuel and develops compensation mechanisms to work with that fuel. So not surprising that just a few days of dropping the carbs is not going to change all that overnight.
I also might add that it is common lore in the lowcarb community (which is mostly not paleo, just lowcarb), that if you let too long go between meals, such that you get really hungry, then this will often trigger carb cravings. ANd I did find that to be true in the beginning especially. YOu will see a bit of this in paleo communities when they say, if you feel a carb craving, you can often kill it with eating fat. After decades of eating sugar, with the body not yet fully adapted to ketosis, I am not surprised that the brain still falls back on the fastest energy source that it knows, and that source is glucose. I suspect that in many of us, storing and removal of fat from fat cells, a process that should be natural and easy, tends to get skewed towards easier storage and slower removal. It takes a while to fix that system, such that you can easily extract fat from fat cells and comfortably use it for energy without feeling weak or tired. I think for many, that ability does not come back in the first weeks of the diet, and so they feel hungry a lot and have to eat regularly. It may take some months to get to that point.
Suffice it to say, that what you feel and how you react in the early days of paleo is not always how you will feel 3 or 4 months down the road. Give your body and brain some time to adapt.
on February 14, 2011
at 08:01 PM
There was a period of a couple of years during which I couldn't get my low carb diet under control for more than a few weeks at best. This was after successfully low-carbing for a long time, but in a different life situation. I was very slowly gaining weight, because I would lose very slowly on VLC, and then go two steps back with a binge or merely a moderate-carb day or two. It wasn't until I went to eating only meat that I was able to get this fully under control. After that, sugar-cravings were an absolute non-issue, unless I experimented with adding a small amount of carbs back (and during pregnancy, which was a completely different ballgame).
I don't know how much carbohydrate you are eating now, but you might try lowering it further, even to just meat for a three-week trial and see how it plays out.
Another possibility, is that there is some particular food item (dairy and nuts are common culprits, but it could be anything you are sensitive to) that is causing the problem. You could try simplifying your diet to just a few foods, and see if it resolves then. A food journal could really help.
on February 14, 2011
at 06:12 AM
After the three-day withdrawal, I found getting past the second week the next hardest. I found dark chocolate helpful, and cheese. The next hurdle I found is six weeks. After a few months, I can do without the chocolate and cheese most days. It just takes time to work through.
If you are trying to exercise, this could be back-firing on you, it takes time to adapt. Here is a quote from Dr. Kurt Harris
"Once you are adapted to low carb intake (it may take 6 weeks or more, so go slowly) your mitochondria, including in your muscles and your brain, will literally proliferate and be more energy efficient. Gradually start doing your workouts with less and less carb consumption prior to exercise, to the point where you are solely working out in the fasting state."
Here is the link to the entire article--I highly recommend reviewing it: