Recently I reported a study showing that post-menopausal women who store fat primarily in their bellies are at increased risk for having heart attacks, even if they are not overweight (Eur Heart, June 30, 2019). Now another study shows that adults under age 50 who were not overweight and reduced their intake of food by 300 calories per day for two years had reduced markers of inflammation that are associated with increased risk for heart disease, cancer, dementia and diabetes (Lancet Diabetes & Endocrinology, July 11, 2019). Their weight dropped by 10 percent, and 71 percent of the weight loss was fat. After two years, they had significantly lowered blood pressure, blood sugar, total and bad LDL cholesterol, markers of inflammation such as CRP, and diabetes scores and raised their good HDL cholesterol and insulin sensitivity.
Calorie Restriction May Prolong Life
Many studies on animals have shown that those on calorie restricted diets live longer, have less diabetes, heart attacks and cancers and look younger. At the Wisconsin National Primate Research Center, monkeys eating only 70 percent of their normal caloric intake have lived much longer and appear younger than those eating their usual diets (Nature Communications, Jan 17, 2017).
Nobody really knows whether calorie restriction with adequate nutrients can prolong life in humans or help to prevent diseases. The leading theory for calorie restriction with adequate nutrition is that it teaches your mitochondria to burn food to produce much lower amounts of oxidants. Mitochondria are the tiny furnaces in cells that turn food into energy. Converting food to energy produces free electrons that form reactive chemicals called oxidants that can bind to and damage DNA and shorten life. Exercise also reduces the amount of oxidants and so should help to prolong life.
Another theory is that excess calories cause fat cells to fill up with fat. Full fat cells produce cytokines that turn on your immunity to cause inflammation that damages all the cells in your body, which would shorten life and cause disease. Anything that prevents excess fat storage should reduce inflammation and thus prolong life. Exercise burns calories, and food restriction lowers calorie intake.
My Recommendations
For several years I have followed studies on intermittent fasting and think that it is the easiest way to eat healthfully while taking in fewer calories. This is what we have done for the last five years:
• Keep tempting but unhealthful foods out of the house (sugared drinks, sugar-added foods, red meat, processed meats, fried foods and most foods made from flour).
• Stock a variety of vegetables, fruits, whole grains, beans, nuts and other seeds.
• On "fast" days (any 2 or 3 days per week), eat a healthful breakfast such as oatmeal and then, for the rest of the day, have small meals or snacks of vegetables, fruit or nuts.
• On non-fasting days, eat your normal main meal or meals before 6PM. Try to include lots of the healthful foods listed above.
• After 6PM, avoid foods and drinks that contain calories. Drink all the water you want.
• Be flexible for social occasions.
