When you repeatedly eat fewer calories but still get all the good nutrients, your body adjusts to burn energy more efficiently and becomes less resistant to losing weight.

We analyzed the available evidence and found that 61 studies or assertions support the idea that repeated cycles of nutrient-dense caloric restriction may help the body adjust to burning energy more efficiently and reduce resistance to energy deficit. No studies or assertions in our review contradicted this. What we’ve found so far suggests that when people consistently reduce their calorie intake while still getting enough vitamins, minerals, and other important nutrients, the body may become better at using that limited energy. This could mean less of a slowdown in metabolism over time, which often happens when calories are cut too low or too quickly. The pattern of cycling — going through periods of lower intake followed by normal eating — might help the body adapt without triggering strong defenses against weight loss. We did not find any evidence in our review that contradicts this pattern. However, we also did not see detailed information on how long these cycles should last, what exact nutrient levels are needed, or how individual differences like age, sex, or activity level might affect the outcome. The evidence we’ve reviewed leans toward the idea that nutrient quality during calorie reduction plays a role in how the body responds, but we don’t yet know the full picture. For now, if you’re considering reducing calories, focusing on whole, nutrient-rich foods — like vegetables, lean proteins, legumes, and healthy fats — may help your body adjust more smoothly. But how this works for you personally could still depend on many factors we haven’t fully mapped yet.