between BMI and attrition in basic training, and conducted simulations examining the effect of an increase in the number of high BMI individuals enlisted. As with the injury analyses, a shift in the distribution of BMI toward heavier recruits had very little effect on attrition risk in men. For women, however, there was a higher risk of attrition in the higher BMI groups. Attrition of women is already nearly twice as high as attrition of men, and to further increase this gender differential is a concern. However, the committee’s projections show that increasing the proportion of high (25 to 34) BMI women from the current 23.6 to 40 percent would result in only a 1 point increase in the attrition rate. There could thus be access to an expanded recruit pool if the Services were willing to accept such an increase in the attrition rate.

Conclusion: Committee projections based on data provided by the Army suggest that a shift toward a higher BMI force would be unlikely to adversely impact injury and attrition risk in men, but might slightly increase the attrition risk in women. It is important to note that this conclusion is based on data from individuals who qualified under the current standard.

Recommendation 5-1: As BMI is less predictive of injury and attrition than aerobic fitness, we recommend that it not be used as a proxy measure for fitness in the military population.

Recommendation 5-2: As a BMI standard is not justified on the basis of links to injury or attrition, we recommend that such links not be used as the basis for any use of BMI.

One final potential rationale for the use of BMI/body fat is as a proxy for appearance and military bearing.

Conclusion: Standards for appearance and bearing are issues of military values and thus are outside the committee’s charge.

The fact that some Services have a more stringent BMI standard for retention than for entry led the committee to review research on the likelihood that individuals will be able to lose weight and maintain that weight reduction over time. That research is generally pessimistic about the prospects for long-term weight reduction. Although a relatively small number of individuals with high motivation and high self-control can lose weight and retain that weight loss through diet and high levels of physical activity, such results are not the norm, and research has not identified programs that have a high likelihood of success for achieving long-term substantial, sustainable weight loss. Given the evidence re-



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