As a pediatrician, I can't help but worry about keeping children at a healthy weight. As everyone knows, being overweight increases the risks of all sorts of health problems, especially as kids grow into adults. I flunk as a pediatrician if my patients start out adulthood already unhealthy.
In the United States, one-third of children are either overweight or obese. In the practice where I work, the numbers are higher--in part because many of our patients, living in inner-city Boston, don't have easy access to healthy fresh foods and safe places to exercise (obesity is a social justice issue, too). So I spend a lot of time talking to parents about what their kids eat and drink. Very often I hear, "But he really doesn't eat very much. I don't understand how he is overweight."
It turns out that not all calories are created equal. As my colleague Dr. David Ludwig wrote in a recent commentary in the Journal of the American Medical Association, we need to stop counting calories--and think more carefully about the foods we eat instead.
That's where the glycemic index comes in.
The glycemic index is a measure of how much glucose gets dumped into the blood when you eat a particular food. Glucose is what the body uses for energy. When there is a whole lot at once, it causes a rush of the hormone insulin--which may not only make you hungrier, but slow down your metabolism. Both work together to make you gain weight.
That's why those 100 calorie "snack packs" of cookies can be such a bad idea. Honestly, you are better off having some peanuts or a piece of cheese for a snack. But, people say, don't peanuts have a lot of calories? Doesn't cheese have fat in it? And that's exactly the thinking that Dr. Ludwig says we need to move away from.
Some fats, like the fat in nuts, avocado or olive oil, are really good for us. And both peanuts and cheese have protein, which our body needs--and it takes longer to digest, making us feel full longer.
Here are some foods that have a high glycemic index:
White bread (and plain bagels)
Baked potatoes (these are really high--try a yam instead)
Corn flakes (even plain!)
Rice cakes (and you thought these were healthy)
White rice (go for brown instead, quinoa, or barley)
Pizza (with white crust, sauce, and cheese)
Gatorade (it's higher than soda, which is already pretty high)
Cookies (and candy and other sweets--including Fruit Roll-Ups)
Here are some that have a low glycemic index:
Apples (fruits in general are good, although watermelon, bananas and raisins are higher)
Vegetables (as long as it's not a potato)
Whole grain bread (or a wheat tortilla)
Beans, such as chickpeas, kidney beans, black beans
Nuts, like peanuts
It's during childhood, especially early childhood, that kids develop the eating habits (and tastes!) that are likely to last a lifetime. Not that we all can't make changes and learn to like things when we are older. But it's so much easier to eat healthy foods, and like them, if you start early--and grow up thinking that they are not only yummy, but ordinary.
To learn more about glycemic index and which foods are healthiest, check out the information on the Harvard School of Public Health website. They also have a list of the glycemic index for about 100 common foods--some of it may surprise you!