How long to diet before taking a break

Take a week or two at maintenance every 6 to 12 weeks of dieting, sooner if hunger, sleep or training fall apart. After about six months, or about 10% of your weight, stop and hold at maintenance for two or three months before you diet again.

Are diet breaks cheating?

People tend to hold one of two views. One says the longer and harder you diet the better, and a week off is a week wasted. The other says you need a break every few weeks or your metabolism will crash. Neither is quite right.

A diet break is like a rest week in a training plan. You don’t get fitter during the rest week, but you can’t train hard for months without one, and the training afterward goes better. On a diet, the break gives your hunger and your energy a chance to recover, and for some people it seems to slow the drop in their burn too.

The MATADOR trial

In 2018 Nuala Byrne and her colleagues published a trial in 51 men with obesity. Everyone ate two thirds of their maintenance calories for a total of 16 weeks. One group did the 16 weeks in a row. The other did two weeks of diet, then two weeks at maintenance, again and again, for 30 weeks in all.

The researchers think the breaks kept the body from adapting as hard, so each week of diet went further. The results come from the men who finished (19 and 17), and the six month follow-up from 28 of them. It was one trial, in men only.

The ICECAP trial

In 2021 Jackson Peos and his colleagues tested breaks in 61 adults who already lifted weights, 32 of them women. One group dieted for 12 weeks straight. The other dieted in four blocks of three weeks, with a week at maintenance after each of the first three, 15 weeks in all.

Both groups lost about the same fat and kept about the same muscle and strength. Their resting burn ended up about the same. But the group with breaks reported less hunger and less desire to eat, and felt more satisfied.

In a closer look at 26 of the athletes, each break week put back about 1.3 pounds (0.6 kg). Their lean mass, which includes water and glycogen, went up by about the same, and their fat didn’t change. During the breaks their hunger and irritability fell, and they felt fuller and more alert.

Refeed days

A refeed is a day or two a week at maintenance, usually with extra carbs, inside an otherwise steady diet. In a 2020 trial, 27 resistance trained adults ate about 25% under maintenance for seven weeks. Half had two high carb days a week at maintenance. Both groups lost about the same fat. The refeed group lost about 0.9 pounds (0.4 kg) of lean mass, against about 2.9 pounds (1.3 kg) for the steady group, and their resting burn fell about half as much. A published comment argued that the lean mass difference was smaller when the data were analyzed differently, and the authors replied.

We’re fairly confident breaks don’t hurt fat loss and make dieting easier for most people. Whether they make it faster, week for week of dieting, is still unclear.

How long can you stay in a deficit?

There’s no fixed limit, and the signs tell you more than the calendar. Take a break sooner if you notice these.

• You’re hungry all day, every day, not just before meals.
• Your sleep has got worse.
• Your lifts are falling, not just stalling.
• You think about food constantly.
• Your trend has stalled for three or four weeks on a log you trust.

The longer you diet, the more your hunger and your burn move against you. In a 2011 study, 50 adults who lost about 30 pounds on a ten week very low calorie diet were still hungrier a year later. That’s a reason to diet in stretches, with time at maintenance in between.

When to stop for longer

The NIH’s heart and lung institute suggests a first goal of losing 5 to 10% of your weight over about six months. In Look AHEAD, the big US trial of coached weight loss, people lost about 8.6% in the first year, and a long-running registry of people who kept weight off found it got easier once they had held it for two to five years.

We’d use that as the shape of a long diet. Lose for about six months, or until you’ve lost about 10%, then hold at maintenance for two or three months, longer if you’re tired of dieting. Then decide whether to go again. Each hold lets your new weight become your normal one, with your habits, your hunger and your clothes catching up.

If you’re already lean, cut shorter and slower. Lean athletes in a 2011 trial kept their muscle at about 0.7% of bodyweight a week and didn’t at 1.4%. Your maintenance calories after a diet covers how to set the number for a break or a long hold.

How to take a break

1. Eat at maintenance. Add back your deficit, about 500 calories for each pound a week you were losing. A break isn’t a holiday from food.
2. Keep the habits. Same protein, same lifting, same steps.
3. Expect a pound or two. It’s glycogen and water, and it goes again in the first week back on the diet.
4. Keep weighing. The trend should be flat after the first few days. If it keeps climbing, you’re above maintenance.
5. Go back on the date you planned. Put it in your calendar before the break starts.