Body weight: implications for the prevention of coronary heart disease, stroke, and diabetes mellitus in a cohort study of middle aged men

Abstract Objective: To determine the body mass index associated with the lowest morbidity and mortality. Design: Prospective study of a male cohort. Setting: One general practice in each of 24 British towns. Subjects: 7735 men aged 40-59 years at screening. Main outcome measures: All cause death rate, heart attacks, and stroke (fatal and non-fatal) and development of diabetes, or any of these outcomes (combined end point) over an average follow up of 14.8 years. Results: There were 1271 deaths from all causes, 974 heart attacks, 290 strokes, and 245 new cases of diabetes mellitus. All cause mortality was increased only in men with a body mass index (kg/m 2 ) <20 and in men with an index ≥30. However, risk of cardiovascular death, heart attack, and diabetes increased progressively from an index of <20 even after age, smoking, social class, alcohol consumption, and physical activity were adjusted for. For the combined end point the lowest risks were seen for an index of 20.0-23.9. In never smokers and former smokers, deaths from any cause rose progressively from an index of 20.0-21.9 and for the combined end point, from 20.0-23.9. Age adjusted levels of a wide range of cardiovascular risk factors rose or fell progressively from an index <20. Conclusion: A healthy body mass index in these middle aged British men seems to be about 22. Key messages The body mass index associated with the lowest mortality and the lowest incidence of coronary heart disease, stroke, and diabetes mellitus is not known In this study of middle aged men the risk of cardiovascular mortality, heart attack, and diabetes increased progressively from a body mass index <20 For a combined end point (heart attack, stroke, diabetes, or death from any cause) the lowest risk was in the range 20-24 Levels of a wide range of cardiovascular risk factors increased progressively from an index of <20 A healthy body mass index in middle aged men seems to be around 22