13 Misleading Food Label Claims and How Not to Be Tricked To use the label low-calorie in the United States, the FDA mandates that foods contain 40 calories or less per reference amount customarily consumed ( RACC ). Meals and main dishes should include 120 calories or less per 100 grams of food. 6. Label Says "Low-Carb" The FDA does not have any guidelines for the labeling of foods as low-carb.