The calories in/calories out model of weight management says: burn more calories than you consume to lose weight; –balance calorie consumption with expenditure to maintain weight. Like the public health ad said that I remember from the Washington subway in the late 90′s: switch from mayonnaise to mustard on your daily sandwich and lose 10.4 pounds a year (savings of 100 calories/day for 365 days). The CDC recommends that children get 60 minutes of moderate intensity physical activity on most days of the week, and preferably every day. For a 154 pound person, they estimate that 60 minutes of brisk walking (4.5 mph) will burn 460 calories an hour (more if you are heavier, less if you are lighter). That’s 3220 calories per week, or 47.8 pounds of expected weight loss over a year.
Virtually all of the dietary advice provided to parents who are trying to help their children achieve or maintain a healthy weight conforms to this model, the most recent and visible example being Michelle Obama’s Let’s Move initiative, which is closely tied to the USDA’s new food plate eating plan, and replaced the earlier pyramid eating plan. Both the new Food Plate and the old Pyramid are high carb, low fat eating plans.
These diets were recommended by public health authorities beginning in the 1980s because it was believed such a diet was beneficial for preventing heart disease, while at the same time controlling weight because it was supposed to be a relatively low calorie diet. Carbohydrates have fewer calories per gram of weight (4) than fat (9) and the same as protein (4). It was further thought that even if the diet itself didn’t turn out to be protective against heart disease, it would control weight, and controlling weight would be protective against heart disease.
There’s just one problem: high carb, low fat diets like the new food plate and the old pyramid don’t work for weight loss or weight maintenance and don’t improve other health markers either. Gary Taubes, in the lengthy “Good Calories, Bad Calories,” and the cliffs notes version “Why We Get Fat and What to do About it,” eviscerates the logic behind low fat, high carb diets. Reading these books completely changed how I thought about Juliana’s struggle with weight. If you eat like the USDA pyramid and are a normal weight, your body can handle a high level of carbohydrates (for now at least)–the evidence for that is that you are a normal weight. Your child can’t, and that is why he or she is overweight.
If you are a normal weight adult trying to help an overweight child, you should run to the library or bookstore for these books.