Lifestyle factors, body mass index, and lipid profile in adolescents.

OBJECTIVE AND METHODS A model specifying body mass index (BMI) as mediating the relationship between lifestyle factors (aerobic fitness determined by peak oxygen consumption; physical activity by 7-day physical activity recall; diet by 24 hr dietary recall), and lipid profile were tested in a sample of 205 adolescents (73% boys), who were on average at risk of overweight, aerobically unfit, and from ethnic minority groups. RESULTS In this well-fitting model, consuming a diet low in fat and cholesterol, and being aerobically fit predicted lower BMI, which together resulted in increases in high-density lipoprotein cholesterol and decreases in triglycerides and low-density lipoprotein cholesterol. Being physically active, predicted greater aerobic fitness. CONCLUSIONS In addition to furthering understanding of the interrelationships among predisposing, major, and conditional coronary heart disease risk factors in adolescents, these data suggest that improving diet and aerobic fitness will reduce BMI and result in a better lipid profile.