The old adage that breakfast is the most important meal of the day is one that Jason Fung, M.D. does not refute; however, what the Ontario-based physician does disagree with is when you actually have your breakfast. “People need to remember that your breakfast is simply just the meal that breaks your fast,” he says.
And fasting is what Fung has become an expert in over the years. As the coauthor of the wildly successful The Complete Guide to Fasting: Heal Your Body Through Intermittent, Alternate-Day, and Extended Fasting, Fung has incorporated the method of intermittent fasting (IF) into his practice and personal life over the last five years. IF or flexible eating is simply the act of eating in a defined window of time and fasting in the other; in other words, a person may eat in an eight-hour window but then fast for the other sixteen hours of the day. For most of Fung’s patients who suffer from type 2 diabetes, the use of IF has become an integral part of their treatment, helping the majority get out of the diabetic range sans the use of medications. “Intermittent fasting is an incredibly powerful tool in dealing with type 2 diabetics and those who are obese,” says Fung. “It helps them lower their insulin levels and lose weight more productively without the use of medications.”
Physiologically, IF allows bodies to dip into their fat stores and use that as energy versus the food that’s consumed. “We are either in a fed or a fasted state,” says Fung. “If we are constantly eating and in a fed state, we’re never able to use our stored fat as energy,” hence why some people are unable to lose body fat. “‘Six small meals a day’ approach is a glycogen roller coaster,” adds Precision Nutrition-certified sports nutritionist Amanda Dale, founder of ThisFitBlonde. “You eat food, your body uses the food for fuel, you eat food again, your body uses the food again; it never ends. Sure, you are continuously eating and burning, but you are never actually attacking your body’s fat stores and never training your body how to convert fat to energy.”
A study in the International Journal of Obesity found that IF was as effective as calorie restriction for improving weight loss, insulin sensitivity, and other health biomarkers (e.g., breast cancer, diabetes, and cardiovascular disease). As it turns out, the benefits of fasting go well beyond weight loss. According to a recent study, Harvard University researchers found that IF can actually slow the aging process, increase lifespan, and improve overall health by altering the activity of mitochondrial networks inside your cells.
On the latter, IF manipulates the mitochondrial networks, which forces them to work harder and essentially keep them in a more “youthful” state. “The results of these short-term controlled fasts have been a decrease in weight and an improvement in blood chemistries, primarily as relates to improved lipid profile, improved insulin sensitivity, and a decrease in inflammatory markers,” explains board certified clinical nutritionist Dr. Stephanie Nielsen, founder and clinical director of Wishing You Wellness, LLC. “All of these lead to the potential for improved health such as a reversal of type 2 diabetes, decrease in autoimmune systems, decrease in blood pressures, and more.”
While more research is needed to support the effects of IF on other diseases, Fung says he’ll continue to prescribe it as a nutritional therapy to his patients suffering from type 2 diabetes, metabolic syndrome, fatty liver disease, and other conditions. Says Fung: “Fasting is such a powerful tool in combatting so many diseases.”