In an agreement brokered by the Alliance for a Healthier Generation (the American Heart Association plus the William J. Clinton Foundation), five food manufacturers have promised to follow new nutritional guidelines for snacks sold in schools. As with the soft drink restrictions it arranged earlier this year, the alliance presents the nutritional guidelines as a way of "combating childhood obesity." But it seems unlikely the changes will make kids noticeably thinner.
The only rule that's directly related to that goal is a per-serving limit of 100 calories for foods other than fruits, vegetables, dairy products, entrees, and items with specified levels of fiber, protein, vitamins, or minerals. The general thrust is to increase the nutrient-to-calorie ratio and to reduce levels of fat, sugar, and salt. But these changes by themselves won't reduce total calorie consumption. The per-serving calorie limit might, but only if kids don't compensate by buying more servings, eating more of the foods not covered by the limit, bringing more food to school, or eating more elsewhere.
I have no problem in principle with agreements like this one, except to the extent that they're prompted by fears of litigation—litigation that would be groundless, in my view, since schools, not food companies, decide what students can buy at school. I'm just skeptical that fiddling with the mix of snacks and drinks sold in schools will have the advertised effect. Although making the food available in schools a little healthier can't hurt, I don't think it's reasonable to expect schools to police kids' calorie consumption.