Obesity in the United Kingdom Armed Forces: prevalence based on measured and self-reported data.

OBJECTIVES To assess the prevalence of obesity in the United Kingdom military and general population and the extent to which self-reported data underestimates obesity. METHODS Height and weight data from military personnel (measured data: 2,073 men, 308 women; self-reported data: 6,374 men, 609 women) and from the general population (measured data: 1,121 men, 1,396 women; self-reported data: 1,234 men, 1,543 women). RESULTS Obesity (defined as having a body mass index of 30+) was 6.2% in those under 25 years old and 24.5% in those over 35 years old in military males, and the prevalence of obesity was 12% in those under 25 years old and 25% in those over 35 years old in military women. Self-reported body mass index underestimated obesity. CONCLUSIONS Obesity is uncommon in those under 25 years old in the United Kingdom military. The prevalence of obesity based on self-reported data underestimates true prevalence.