[Obesity and osteoporosis: effect of weight variation on bone mass].

Obesity and osteoporosis are both chronic conditions with multi-factor aetiologies and a considerable associated level of morbidity and mortality. They are endemic in economically developed countries. Various epidemiological studies have indicated an overweight condition to have a protective effect on the occurrence of osteoporotic fractures, but the data available on the effects of weight loss on the conservation of bone mass are scant and fragmented. The present review attempts to give a critical assessment of the published trials that have analyzed the evolution of bone mass during the administration of low calorie diets to obese females, as well as to identify those aspects that would deserve special attention in the planning of future research in this field.