Why Calorie Counting Doesn’t Work

I have always hated counting calories, whether it’s to lose weight or gain weight. First of all, it’s tedious. Second, when I am ready to eat, I don’t want to bother weighing and measuring my food first — I just want to eat! (Also, remember that when you eat fewer calories, your body tries to burn fewer calories, too, which can lead to a frustrating cycle of eating less and less while not losing much weight.)

I’ve never advocated that my clients count calories, either. Instead, I encourage them to shift their diet toward more healthy foods — whole, unprocessed foods that they cook for themselves, as opposed to prepackaged, processed, “edible food-like products.”

My girlfriend recently sent me an old blog post from Discover Magazine that illustrates why counting calories often doesn’t work very well (and provides some very interesting side notes along the way):

1. In many cases, cooked foods provide more energy than raw foods. Cooking changes the structure of starches (found in wheat and potatoes, for example), making them more easily digested in your body.
2. In a controlled study, mice preferred to eat cooked beef and cooked sweet potatoes vs. raw beef or raw sweet potatoes. They also gained more weight when eating the cooked foods (or lost less weight). Maybe they preferred the aroma and the taste, or maybe it was something else. (I’m not sure how this works, given that I wouldn’t expect mice in the wild to eat a lot of cooked food.)
3. The US uses the Atwater Convention for measuring the calorie content of foods. This is a very old system that assigns 4 calories to every gram of carbohydrate, 4 calories/gram of protein, and 9 calories/gram of fat. But this presents two big problems:
   

   First, it pays no attention to the extent to which food has been processed. For example, it treats grain as the same calorie value whether it is eaten whole or as highly milled flour. But smaller particles are less work to digest, and therefore provide more net energy. Second, it treats foods as equally digestible (meaning, having the same proportion digested) regardless of processing. But cooked foods, as we’ve seen, are more digestible than raw foods.

   In other words, the Atwater Convention probably leads to underestimating calories in highly processed foods, and overestimating calories in whole, unprocessed foods.

The blog post ends with the conclusion that if you want to lose weight, you might want to eat mostly unprocessed, raw foods (such as carrots). If you want to gain weight, you might want to cook those same foods, so you can get more calories out of them.

Of course, I don’t want any of my clients to go on a 100% raw food diet. Some foods are more nutritious when cooked (e.g., tomatoes). Some vegetables may be more healthy when raw (e.g., broccoli). And some vegetables may lose vitamin C when cooked, but release more of other nutrients (e.g., lycopene from tomatoes). So it’s probably best to eat a mix of cooked and raw foods, and not worry about it too much.

That said, if you are very diligent, and you are the hyper-organized, spreadsheet-loving type, counting calories can work. I’ve noticed that it tends to work better in people who already eat pretty well, and who eat mostly the same things every day. That way, even if the Atwater Convention is inaccurate, you’ll be using the same inaccurate measurement for the same foods, so you’ll have a more useful comparison (e.g., 4 oz. vs. 6 oz. of chicken thighs, as opposed to 4 oz. of chicken thighs vs. 5 oz. of processed turkey breast).

So if you want to lose weight, try shifting your diet to more unprocessed foods, and add a few more raw vegetables, and see what happens!