Q: I've heard about the "calorie cycling diet." What exactly is calorie cycling? Is this an effective way to lose weight?

A:Calorie Cycling (calorie shifting, or zig-zagging) is a method used by some to avoid a weight-loss plateau, when your body gets to a point that it is difficult to lose more pounds. The idea behind calorie cycling is to count your calories each day, and cycle between higher- and lower-calorie days, in order to trick your body's metabolism and keep it guessing. The purpose is to keep your body from getting into "starvation mode," which causes your body to slow down its own metabolism in response to a lack of calories. 

 

There are various methods to determine your calorie cycling levels each day, according to several authors on the subject. The calories usually equal a typical calorie deficit during a 1-week period (3500 calories=1 pound), but include a couple of high calorie days to raise leptin (an appetite suppression hormone) levels and prevent "starvation mode." 

 
There is plenty of research documenting the "starvation mode" that results from a very-low calorie diet. However, there is little to no clinical research about calorie cycling to prove that it is effective. Most of the literature is anecdotal, with personal stories of weight loss.  Additionally, the need to closely count calories every day can make adherence to calorie cycling difficult. Moreover, designating a day to "cheat" may trigger overindulgence and overeating. The bottom line is: Science has taught us that sustained weight loss is achieved through a moderate calorie deficit, regular physical activity, and small dietary indulgences versus full-blown "cheat days." -- Helen Moseley, M.S., R.D.