The rise of childhood obesity has been on the radar of key policymakers for years. But this month, the U.S. Department of Agriculture took action by issuing new rules that drastically reduce the presence of foods deemed unhealthy within a school's four walls.

These strict provisions were created with the idea that reducing a student's exposure to advertisements of foods not permitted for sale in school according to the guidelines will reduce the appeal for these items and thus help them make better, healthier choices.

Unhealthy foods are those viewed as having too many calories and too much sodium, fat, and/or sugar. The new limits for snacks and entrees are now defined as:

• Calories: Snacks must have less than 200 calories and entrees must have less than 350
• Sodium: Snacks must have less than 280mg and entrees must have less than 480
• Fat: Both snacks and entrees must have a total fat of less than 35% of calories, saturated fat of less than 10% of calories, and zero grams of trans fat
• Sugar: Both snacks and entrees must have less than 35% of weight from total sugars in food.