For 40 years, I have been telling people how important breakfast is. Even worse, in that know-it-all fashion that physicians use to speak to their spouses about health, I have been telling my wife, who often skips breakfast, what a mistake she has been making. It turns out that for most of us, the advice to never skip breakfast may be just another medical myth.
About six months ago I noticed that someone I knew was looking much thinner. I asked her if she was “OK.” She replied that she felt better then she had in years and that her weight loss was due to the 5:2 intermittent fasting (IF) diet. I know that fasting is part of many religions but I had always thought of this as more important in spiritual terms then in physical terms.
I asked what a 5:2 diet is. She said that for one to two days a week she only eats about 500 calories — which is basically just one light meal for lunch or dinner. The rest of the week she eats her normal diet. She did say that she tried to keep the normal diet low in white carbs and processed foods but she is not a fanatic about this.
I stored away this new knowledge and then about a month later came across a YouTube video made by a British journalist entitled “Eat, Fast and Live Longer.”
He was out of shape and somewhat overweight. He decided to make a video of his exploration of the science behind intermittent fasting and of his own attempt at following this eating pattern.
In his video he interviews a few of the most well respected researchers in this field and then, using their recommendations, goes on a five-week program of intermittent fasting. At the end of five weeks he had lost a significant amount of weight and his blood tests showed marked improvement in the control of blood sugar, lipids and cancer markers. I thought it interesting, so, once again, I stored it away in the dusty bin of my memory.
Then in March 2016 The New York Times had an article entitled “Fasting Diets are Gaining Acceptance.” The article begins by describing Mark Mattson. He is chief of the neuroscience lab at the National Institute on Aging in Maryland and has not eaten breakfast in 35 years.
The work by his lab and other labs such as the Longevity Institute at the University of Southern California have been confirming the following findings in their studies of mice and humans. As little as two to five days of IF per month has been associated with the following:
1. Significant weight loss;
2. Reduced biomarkers for diabetes, cancer, inflammation and heart disease;
3. Reduced blood pressure;
4. Protection from strokes, Alzheimer’s and Parkinson’s disease in mice.
There is now a growing interest in finding out why IF has such positive effects on the bodies of lab animals and humans and what is the best pattern of eating?
Current thinking includes the idea that all animals evolved with eating patterns of feast or famine. For most of human history, mankind did not have access to three meals plus snacks per day.
It appears that our bodies are designed to withstand periods without food and it is also obvious that too much food is injuring our health. Steady eating throughout the day produces a large amount of insulin, which promotes more eating and the deposition of fat.
A good way to get rid of fat appears to include allowing yourself to get hungry. When we fast we apparently switch from burning sugar for fuel to burning fat. We also decrease the levels of hormones that are associated with cancer, diabetes and aging in general.
It also appears that fasting stresses cells which prompts the cells to produce protective substances. These substances may help protect against aging, auto-immune diseases such as lupus and even other pathologic conditions such as Alzheimer’s.
The research on calorie restriction in animals is fairly extensive and steadily increasing. The research on humans is accelerating rapidly. An excellent review article concerning this research was written by Mark Matson, et al, entitled “Meal Frequency and Timing in Health and Disease.” It discusses variations of the diets described below.
1. “The 5:2 Diet” consists of five days per week of a normal diet and two days per week of eating just a light meal (500-600 calories) usually for lunch or dinner, and no other food for that day. The two days can be one after another or separated.
2. “The Restricted Time of Eating Diet” consists of skipping breakfast and eating all your food for the day in the hours from about noon to 6 or 8 p.m. That results in a daily overnight fast of 16 to 18 hours.
Advice about these patterns of eating includes statements that they should not be followed by pregnant women and that people with diabetes and others on medication should discuss fasting diets with their physicians.
Common advice also includes expecting that it may take one to two weeks to get used to such a pattern; that these are general guidelines only and can be altered; and most importantly, fasting diets are certainly not for everyone.
Dr. Lee Evslin is a retired physician. He has lived and practiced on Kauai since 1979. He also served as the CEO of Kauai Medical Clinic and Wilcox Hospital. His regular column presents new ideas on health-related issues.