Lack of sleep spells trouble for avoiding obesity in several ways. It increases
ghrelin (that makes you hungry), increases cortisol, reduces leptin, and activates the
reward system that, in turn, increases the desire for comfort foods. A study of the
role of sleep in obesity published in the European Journal of Clinical Nutrition that
analyzed intervention trials found that lack of sleep led to overeating the next
day by an average of 385 calories. The study was short term, so the implications
for long-term weight gain are uncertain. However, other studies suggest that lack
of sleep disrupts the reward center of the brain.

I know that when I was a somewhat groggy medical intern working in a hospital
with very little sleep, I ate more than usual in an attempt to feel better. Future blogs will discuss the many reasons to get
enough sleep—to help avoid overweight and obesity is on the list.

The microbiome and adiposity
An additional complication concerning the metabolism of food and absorption of
food calories is evidence that the genes in the bacteria in your body, the microbiome,
may play an important role in the genesis of obesity and type 2 diabetes.
That gut bacteria synthesize essential vitamins and amino acids and help degrade
toxins is well known. Research has shown that the many genes in a human’s microbiome
(250 to 800 times the number of human genes) allow bacteria to synthesize
proteins, including hormones, neurotransmitters, and molecules causing inflammation,
that can enter the circulation and affect health.

Human gut enzymes are unable to digest many of the dietary polysaccharides in
fiber, but microbial enzymes can make them into digestible monosaccharides and
short-chain fatty acids. The microbiota influences the calories the body absorbs, but
more research is needed to understand this phenomenon. Farmers give livestock
and poultry antibiotics because it makes them grow fatter. And various animal experiments
suggest that microbiota may affect obesity in mammals. The type of bacteria
that is predominant in the gut is affected to some extent on the nature of your
diet, depending on if your diet is based on animal fat and protein or plant foods.
It is possible that manipulation of the microbiome with antibiotics, probiotics (live
microorganisms), or other means could affect the risk of obesity, but biomedical
science is still learning how to do this.

This blog presents opinions and ideas and is intended to provide helpful general information. I am not engaged in rendering advice or services to the individual reader. The ideas, procedures and suggestions in that are presented are not in any way a substitute for the advice and care of the reader’s own physician or other medical professional based on the reader’s own individual conditions, symptoms or concerns. If the reader needs personal medical, health, dietary, exercise or other assistance or advice the reader should consult a physician and/or other qualified health professionals. The author specifically disclaims all responsibility for any injury, damage or loss that the reader may incur as a direct or indirect consequence of following any directions or suggestions given in this blog or participating in any programs described in this blog or in the book, The Building Blocks of Health––How to Optimize Your Health with a Lifestyle Checklist (available in print or downloaded at Amazon, Apple, Barnes and Noble and elsewhere). Copyright 2021 by J. Joseph Speidel.