Over the past 10,000 years, our genes depended on a lifestyle that had a different daily caloric intake. Some days were a feast and other days were close to fasting, especially during prolonged hunts. Most days provided a modest intake, largely from gathering familiar foods. Yet over the last 20-40 years, our daily calorie intake has become remarkably consistent, and at the same time our waistlines have expanded.
For years, neuro scientists have advocated regular fasting to help prevent memory loss. Recently, a variety of studies have shown that cutting down on caloric intake might slow aging. More evidence suggests that varying caloric intake from day to day may help with blood sugar and weight control.
As the evidence grows, I’ve been wondering if we should all be doing a partial fast (800-1000 calories per day) at least 1-2 days per week, especially for people who have trouble losing weight, have memory problems, or have problems with blood sugar control. For those of us with routine eating times, a semi-fasting day also gives us the chance to appreciate food more and deal with hunger in a new way.
Last week my son, a biology major at the University of South Florida (who has helped me publish research studies), sent me an e-mail suggesting we do a study at our clinic on modifying calorie intake. He referenced an article that was written in Medical Hypotheses (Johnson JB, Laub DR, John S. The effect on health of alternate day calorie restriction: eating less and more than needed on alternate days prolongs life. 2006.) The authors shared their results from alternatively feeding elderly people 900 calories or 2300 calories every other day for three years. They compared this plan to another elderly group eating the same 1600 calories every day. Those having the varied calorie intake showed much better health results (fewer deaths and hospitalizations, plus better weight control and blood sugar control) compared to those eating the same calories daily.
The key with this type of semi-fasting would be to meet your nutrient needs and protein requirements so that you maintain a healthy metabolism and maintain your ability to detox away toxins that are released from fat.
So I’m finally committed. I’m going to make Tuesdays my partial fast day, and try this for a few months. I’ll aim to add some Thursdays as well. I’ll take my multivitamin, enjoy three protein-fiber shakes per day, and drink more water. I’ll continue to enjoy a couple cups of coffee and green tea each day. My genes hopefully will appreciate the calorie intake variation and in theory, this should make my metabolism and hormonal balance more efficient, slow my aging process and enhance my mental function. I am hoping to lose a few pounds also.
Obviously, this isn’t a formal study, yet I invite you to try this with me 1-2 days per week and send me comments on your results.
Below is a sample protein-fiber shake recipe that you can use.
Protein-Fiber Smoothie: In a blender, combine the following and blend until smooth.
– 1-3 scoops of protein powder (such as whey protein, Thorne’s VegaLite Protein, or UltraMeal360 with 20-30 grams of protein per shake)
– 8 ounces (calcium fortified almond or soy milk, or organic non-fat milk)
–1 cup frozen fruit (such as blueberries, strawberries, or peaches)
– 1/2 to 1 scoop fiber (4-8 grams of fiber, such as Thorne’s Medibulk fiber)
– 1/2 cup ice (or water or green tea)
Each shake provides about 300 calories and 7-10 grams of fiber. Enjoy one shake three times per day on your semi-fasting day. OK to have black coffee or green tea, plus 6 glasses of water over the day.
To Your Health,
Steven Masley, MD, FAAFP, CNS, FACN