Being overweight or obese is the leading medical reason that young adults cannot join the military, with 1 in 4 too overweight to enlist, says a report issued today by Mission:Readiness, a group of more than 300 retired generals and admirals.

Schools are selling 400 billion calories of junk food every year—the equivalent of nearly 2 billion candy bars—says Still Too Fat to Fight, which calls for stronger standards for foods and beverages sold at schools.

According to the report, the military spends over a billion dollars a year on weight-related diseases. "Because our country has failed to improve fitness and reduce obesity among our youth, the military has had to work much harder than in the past to recruit and retain enough qualified men and women who can effectively serve our country," the authors say.

This month the Centers for Disease Control and Prevention (CDC) is highlighting the critical role that schools play in improving the physical activity and dietary and behaviors of children and adolescents. CDC has synthesized research and best practices related to promoting healthy eating and physical activity in schools, culminating in 9 guidelines.

Each of the guidelines is accompanied by a set of implementation strategies developed to help schools work toward achieving each guideline. For example, strategies to achieve guideline 4, which calls for the implementation of a comprehensive physical activity program with high-quality physical education as the cornerstone, include requiring students in grades K-12 to participate in daily physical education that uses a planned and sequential curriculum and instructional practices that are consistent with national or state standards for physical education, providing a substantial percentage of each student's recommended daily amount of physical activity in physical education class, and using instructional strategies in physical education that enhance students' behavioral skills, confidence in their abilities, and desire to adopt and maintain a physically active lifestyle.