Losing weight is a balancing act. 

On the one hand, the faster you lose weight, the more excited you are to continue, but on the other hand, the faster you lose weight, the more you run the risk of muscle loss, hunger, irritability, metabolic slowdown, and eventually eating your way back to your previous weight (or even heavier).

One way to thread this needle is to maintain a fairly aggressive calorie deficit (20-to-25 percent) and take periodic breaks from your diet—an approach has been validated by a University of Tasmania study where scientists found that taking short, planned, highly structured breaks from dieting made fat loss more efficient and sustainable.

In this study, researchers split fifty-one men into two groups: one group dieted every day for sixteen weeks, and the other dieted on a “two week on” (calorie deficit), “two week off” (maintenance calories) schedule until they also reached sixteen weeks of dieting (the second group taking twice as long). 

The researchers provided all of the meals to the subjects throughout the study, which ensured they were eating the right number of calories, and everyone also kept a food diary to be doubly sure of how much food they were eating.

By the end of their weight loss phases, participants in group one (continuous dieting) who completed the study lost about 21 pounds on average, and their counterparts in group two (intermittent dieting) lost nearly 32 pounds. Then, all participants returned to their normal eating patterns, and six months later, the researchers checked in with everyone to see how much weight they had regained.

The scientists found that the continuous dieters had regained 13 pounds on average, reducing their total weight loss to just over 7 pounds, and the intermittent dieters had regained just under 8 pounds, pegging their net weight loss at about 24 pounds.

So, in the final analysis, the intermittent dieters outperformed the continuous dieters in all respects, but there was one catch: It took them twice as long to complete their weight loss phase and return to normal eating. And in the real world, doubling the duration of a diet can make it more daunting and difficult to stick with.

Be that as it may, how can you effectively incorporate the findings of this study into your own dieting? 

While you don’t need to use diet breaks if you don’t want to, they can be a gamechanger if you’ve struggled with sticking to a diet in the past and especially if you’ve struggled to maintain weight loss over the long haul. 

Here’s what works well for most people:

  1. If your body composition goal requires no more than eight-or-so weeks of dieting, you probably don’t need to include any breaks. Just stick it out.
  2. If your goal requires more than eight-to-twelve weeks of dieting, take a one-to-two week diet break (maintenance calories) every eight-to-ten weeks.
  3. If you’re lean (25 percent body fat or less for women and 15 percent or less for men) and looking to get really lean, take a one-week diet break every six-to-eight weeks.