Effect of Calorie Restriction on Bone Mineral Density (6-month trial)

Researchers studied overweight adults who followed a calorie-restricted diet for six months. They measured bone mineral density, meaning how much mineral is packed into the bones, using a low-dose X-ray scan. The study found that losing weight through calorie restriction could reduce bone density, especially at some areas such as the hip. Because the trial was short and small, it could not show whether this would lead to more broken bones later.

What this means for you: This is a reason to avoid crash diets and to protect bone health with enough protein, calcium, vitamin D, and weight-bearing exercise. It does not show that sensible weight loss is unsafe, but it does suggest that rapid or severe calorie restriction may carry a bone cost.