New Year’s resolutions have come and gone, but some folks may still be searching for the perfect program to drop weight. As a Registered Dietitian, I am continuously confronted by clients who want to follow the newest and most popular (or not so popular) fad diets. Intermittent Fasting (IF) alternates between periods of eating and fasting. During this program, you fast twice a week with each fasting period lasting 16 to 24 hours. For example, after dinner tonight, you’d go to sleep, skip breakfast and lunch and end your fast period with dinner the next day. This routine would be repeated again later that week. The idea behind IF is that your total caloric intake will be less, because you are skipping meals for two whole days.
There is not a lot of literature and evidence to support intermittent fasting as a safe, effective approach. However, here is what we know about IF so far.
IF may lower prevalence of coronary artery disease and diabetes – There have been a number of studies done on animals that suggest IF may improve health conditions such as obesity, diabetes and cardiovascular disease. Bottom Line: More studies need to be done in order to recommend IF as part of a healthy lifestyle.
IF may compromise lean muscle tissue – If the body does not have the appropriate carbohydrate stores for fuel, your body will digest your lean muscle tissue! Bottom Line: Muscle weighs more than fat, so don’t get all wrapped up with the numbers on the scale. Focus on body fat percentages. Combine IF with resistance training to maintain lean muscle mass but don’t expect your percentage of fat mass to decrease if you don’t include strength training.
IF may be risky for those on Medical Nutrition Therapy – IF may be risky for those with clinical diagnosis such as diabetes or hypoglycemia. Bottom Line: Consult with your doctor and a Registered Dietitian before implementing this program to be sure it’s safe for you.
IF may promote unhealthy eating behaviors – The idea of IF is to restrict calories over the course of the week, since you are not eating for two whole days. This is not a good strategy for weight loss if you are eating more calories, or binge eating, on the days after your fast. Bottom Line: It’s all about calories in and calories out; for weight loss you need to burn more calories than you consume. A balanced eating plan with nutrient dense foods along with exercise is the safest route to drop weight. IF is already built into your day, during the hours you sleep at night.
IF can be challenging to maintain during the chaos of life – Don’t set yourself up for failure before you even begin. Kids have school/athletic functions, your friends invite you to happy hour, work requires you to travel, family birthday parties come in cluster – life will always present you with times you need to be flexible. An inflexible eating plan doesn’t help. Bottom Line: Our exercise and eating regimes need to be altered around life. You won’t be perfect, but aim high 80% of the time and leave the other 20% to make memories.
Bottom Line to the Bottom Line: There is no magical formula to weight loss. The fact of the matter is, if you want to drop weight, lower body composition and excel at your sport, you need to make balanced choices – eat less calories for weight loss, eat less and do more strength training for a better body composition and fuel frequently to keep energy stores full to optimize sports performance. Contact Christine Turpin to dial in your nutrition and athletic performance through a sound eating plan.
Christine Turpin, RD, CSSD, LDN, CSCS
Board Certified Specialist in Sports Dietetics
Tinsley, Grant M., Natalie K. Butler, Jeffrey S. Forsse, Annie A. Bane, Grant B. Morgan, Paul S. Hwang, Peter W. Grandjean, and Paul M La Bounty. “Intermittent Fasting Combined with Resistance Training: Effects on Body Composition, Muscular Performance, and Dietary Intake.” Journal of the International Society of Sports Nutrition 12.S1 (2015): n. pag. Web.
Horne23*, Benjamin D., and Joseph B Muhlestein24 And. “Benjamin D Horne.” Health effects of intermittent fasting: hormesis or harm? A systematic review The American Journal of Clinical Nutrition. N.p., n.d. Web. 27 Mar. 2017.