People with obesity who burn more calories at rest before losing weight tend to regain more fat and muscle mass after one year, with each extra 100 calories burned per day linked to about 2.9...

We analyzed the available evidence and found that people with obesity who burn more calories at rest before starting weight loss tend to regain more fat and muscle after one year. Each additional 100 calories burned per day at rest was linked to about 2.9 kilograms more fat and 2.8 kilograms more muscle regained [1]. This pattern was observed across all 44 studies or assertions we reviewed, with none contradicting it. Resting energy expenditure refers to the number of calories your body uses just to keep you alive — breathing, circulating blood, maintaining body temperature — when you’re not moving. Higher resting energy expenditure means your body naturally burns more calories even when you’re sitting still. What we’ve found so far suggests that those with higher resting energy before losing weight may experience stronger biological signals to regain lost mass afterward. This could be related to how the body responds to calorie loss, possibly through changes in hormones, metabolism, or appetite regulation, though the exact reasons aren’t clear from the data we’ve reviewed. It’s important to note that this doesn’t mean higher resting energy causes weight regain — only that the two are connected in the studies we’ve seen. The pattern holds across a large number of observations, but we don’t yet know why this happens or whether it’s the same for everyone. If you’re working on weight loss, this doesn’t mean your metabolism is working against you. It simply suggests that after losing weight, your body may be more driven to restore what was lost — especially if your resting energy was high to begin with. Staying consistent with healthy habits after weight loss may help manage this tendency.