Taking a two-week break from dieting can boost weight loss be 50 percent, recent research finds.
Stopping the diet for a couple of weeks also helps people maintain their weight loss in the long-term, the study found.
Taking a break works because the body gets used to a diet and starts to slow the rate at which it burns calories.
The break, though, brings the metabolism back up to normal speed.
When dieting resumes, weight loss is boosted.
Professor Nuala Byrne, the study’s first author, explained:
“When we reduce our energy (food) intake during dieting, resting metabolism decreases to a greater extent than expected; a phenomenon termed ‘adaptive thermogenesis’ — making weight loss harder to achieve.
This ‘famine reaction’, a survival mechanism which helped humans to survive as a species when food supply was inconsistent in millennia past, is now contributing to our growing waistlines when the food supply is readily available.”
The results come from a study of 51 men who either dieted continuously or took two weeks off at a time.
The design of the study ensured both groups dieted for the same amount of time in total — the only difference was the breaks for one group.
The results showed that those taking a two-week break lost 30 pounds in comparison to just 20 pounds in the continuous dieting group.
Those dieting intermittently were also able to maintain 18 pounds more weight loss after the main block of dieting finished.
Professor Byrne said that shorter breaks from dieting, though, are not as effective:
“There is a growing body of research which has shown that diets which use one to seven day periods of complete or partial fasting alternated with ad libitum food intake, are not more effective for weight loss than conventional continuous dieting.
It seems that the ‘breaks’ from dieting we have used in this study may be critical to the success of this approach.
While further investigations are needed around this intermittent dieting approach, findings from this study provide preliminary support for the model as a superior alternative to continuous dieting for weight loss.”
About the author
Psychologist, Jeremy Dean, PhD is the founder and author of PsyBlog. He holds a doctorate in psychology from University College London and two other advanced degrees in psychology.
He has been writing about scientific research on PsyBlog since 2004. He is also the author of the book “Making Habits, Breaking Habits” (Da Capo, 2003) and several ebooks:
- Accept Yourself: How to feel a profound sense of warmth and self-compassion
- The Anxiety Plan: 42 Strategies For Worry, Phobias, OCD and Panic
- Spark: 17 Steps That Will Boost Your Motivation For Anything
- Activate: How To Find Joy Again By Changing What You Do
The study was published in the International Journal of Obesity (Byrne et al., 2018).