The committee focused on two medical issues for which medical waivers from disqualification are commonly sought: BMI/body fat and diseases of the lungs.

Body Composition and Body Fat

The percentage of children and adults who are overweight or obese is a growing problem in the United States. Widely endorsed definitions categorize a BMI between 25 and 29.9 as overweight and 30 or greater as obese. Among adolescents, the BMI level that identified the highest 5 percent of the population in 1963 is now exceeded by 15.5 percent. The prevalence of obesity is greater for Mexican American and black children than for their white counterparts.

Standards for BMI and body fat are determined by each Service. Current standards could temporarily disqualify 15 to 25 percent of the male and 25 to 50 percent of the female youth population. It is important to note that the BMI standard for remaining in the military is often different from the entry standard. For men, the retention standard is generally more stringent than the entry standard; 25 to 40 percent of the youth population would not meet the retention standard. For women, some Services impose a modestly more stringent retention standard and some a modestly less stringent standard.

One argument for a BMI/body fat standard is the research linking overweight to long-term health outcomes. We note, however, that the vast majority of enlistees serve a single tour of duty, while the negative health outcomes of being overweight tend to emerge much later in life. Thus the committee focused on consequences of being overweight for outcomes during military service.

A second argument is that BMI/body fat is a proxy for physical fitness and is an indicator of risk for injury. The committee reviewed research examining the relationship between BMI and a direct fitness measure and injuries. Although there is a systematic relationship between fitness and injury for both men and women, there is virtually no relationship between BMI and injury rates for men, and the small relationship observed for women reflects a slightly higher injury rate for low BMI (i.e., very lean) women. The committee conducted a series of simulations to project the change in injury rates should the Services increase the number of high BMI individuals enlisted; our findings show that injury rates would change minimally.

Another potential argument is that BMI/body fat is a predictor of attrition. The committee reviewed research examining the relationship

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