Obesity: a certain and avoidable cause of cancer
Menée au Royaume-Uni auprès de plus de 5 millions d'individus, cette étude évalue l'association entre l'indice de masse corporelle et le risque de 22 types de cancer
Body-mass index (BMI) is a simple and commonly used measurement in clinical medicine and population health—a ratio of weight (kilogrammes) and height (metres squared). Adults with a BMI of 25—29·9 kg/m2 are considered overweight and adults with a BMI of 30 kg/m2 or higher are considered obese. The causes and consequences of overweight and obesity, however, are anything but simple. Determinants of BMI include genetic and epigenetic factors; individual behaviours (eg, physical activity, sedentary time, and caloric intake); sociocultural factors; and the physical, economic, and policy environments. Excess adipose tissue is not a benign storage depot for lipids.1 Indeed, overweight and obesity were estimated to cause 3·4 million deaths worldwide in 2010.2 The proportion of adults who were overweight or obese worldwide increased markedly from 1980 to 2013, with parallel increases in children and adolescents.3 Although the causes of these disturbing trends are multifactorial, they almost certainly include the wide propagation of cheap, calorically dense, and nutritionally poor food and drink.4, 5 The well-established associations between high BMI and increased morbidity include coronary heart disease, type 2 diabetes, high blood pressure, stroke, dyslipidaemia, and osteoarthritis. Studies published during the last two decades have added certain cancers to this list.6, 7
The Lancet , commentaire, 2013