Why Low Carb Diets Reduce Hunger

The most amazing thing to me about the low carb lifestyle is that those constant hunger pangs have simply disappeared. Not only that, but I now feel full after eating, which never really happened before. I used to blame my upbringing (both my parents were obese) for damaging that switch in my body that told me I had eaten "enough."

Now I know it has to do with leptin resistance. In the briefest of terms, leptin is a hormone secreted by fat cells and this hormone "tells" the brain that you are full. Most obese people secrete adequate amounts of leptin but, as in the case with insulin, they become insensitive to leptin (just like type II diabetics produce insulin, but they become insensitive to insulin). Tryglycerides are apparently a major problem in leptin resistance. When triclyceride levels increase, so does resistance to leptin. Overweight and obese people usually have quite high triglyceride levels. A low carb diet will reduce triglyceride levels quite rapidly (usually within a few days or a week or two), which then makes you more sensitive to leptin. And then you start to feel full.

This is one reason why people who eat until they are full on a low carb diet spontaneously consume fewer calories than those who eat until they are full on a low fat, high carb diet, and perhaps explains the greater success rate of shedding pounds with a low carb diet.

But there is one additional problem. While you are losing weight, you won't be hungry. However, when you have reached your goal, you will have lost most of your excess fat stores, which are largely responsible for the release of the hormone leptin. There is a three-fold solution to this problem. First, maintain the low carb lifestyle. Second, eat more slowly during meals. And third, go five to six hours between meals without eating. This allows the leptin receptors to reset themselves naturally in the absence of excess fat stores.

More Interesting Research Articles

Leptin is the hormone that is released in your body to tell you that you are full, and don't need to eat anymore.  However, in obese people, leptin can be be overridden by the pleasure center in the brain, and this condition is called leptin resistance.  Most obese people have high levels of leptin in their systems, but this is overridden by the pleasure center in the brain, and they don't feel full.  Now a study in the British Journal of Nutrition shows that a high fat, high sugar diet directly leads to leptin resistance.  The authors even use the word "cause" to describe this relationship.  Further, when a high fat, no sugar diet is introduced, within three days, leptin resistance was reversed.  They identify high fructose corn syrup as a major contributor to leptin resistance.

Another study found that routine, periodic fasting is good for your heart and your health.  Conducted by Intermountain Health Care and funded by the "Deseret Foundation," you know there are Mormons at the heart of this study, scientifically legitimizing the monthly fast.  Still, I find it interesting.  Since being diagnosed as a diabetic in 2002, I have had an extremely hard time with the monthly fast, giving it up altogether some time around 2003.  I felt shaky, weak, and generally awful during the fast.  I chalked this feeling up to being diabetic, but looking back on it now, I realize it was because I was "starving" at the cellular level, since most of my carbohydrate intake was being stored as fat and not used as fuel. Adding fasting on top of cellular starvation was extremely unpleasant.  Last month, however, I decided to try to fast again, and it was surprisingly easy, especially compared to how lousy fasting made me feel until I switched to a low carb regime.  Fast Sunday is again this coming Sunday and I am actively looking forward to the opportunity to fast again.

The paleo nutrition web sites are all about something they call "intermittent fasting," since this is what our hunter/gatherer ancestors had to do on a regular basis, when they couldn't kill food.  Some suggest they didn't eat all that regularly, and when they killed something, they gorged on it, but may have eaten two days out of three, and perhaps only once or twice a day on the days they did eat.  Hence, the interest in intermittent fasting.

All of these insights in this post today come from the remarkable Michael R. Eades, M.D., whose blog and twitter page are amazing sources of information.