Counting Calories: Imprecise Yet Effective

By Kevin Kolodziejski

I bet that ancient Greek Sisyphus had killer quads, hellacious hamstrings, and the power-to-weight ratio of a cycling pro. If Zeus forced you to roll a boulder up a hill in Hades for eternity, I bet you would too.

As a result of this punishment, we use Sisyphean to describe a task that seems endless and futile. It’s the word one well-read member of the first health-and-wellness master’s equivalency course I taught used when I encouraged the class to purchase a food scale, start a log, and count calories as a way to monitor their weight.

And even though I still give that same advice to this day, there’s no denying he had a point.

FDA regulations require food processors to list calories per serving along with other Nutrition Facts information on product labels, but the options the FDA offers food processors to do so are all to some degree estimates. According to ScientificAmerican.com, most food processors use the Atwater system in which 1 gram of protein equals 4 calories, 1 gram of carbohydrates 4, and 1 gram of fat 9.

Each of these three numbers, though, is an average, which means the number of calories listed beside Amount Per Serving is an estimate (and generally a low one). For instance, one serving of a generic wheat and bran flakes cereal claims 120 calories per serving, yet when you do the math for yourself according to the Atwater system and the grams of fat, carbohydrates, and protein listed per serving, you get a number 20 percent higher.

This sort of problem does indeed make cal counting seem Sisyphean.  And there are more.

A study published in the Journal of Nutrition in 2008 determined that whole almonds have about 20 percent fewer calories than the number used on labels. But the Atwater system isn’t to blame here. The research found that some of the fat in almonds cannot be assimilated by the digestive system and is passed instead. So that one ounce of almonds you eat as your mid-afternoon snack really doesn’t contain the 162 calories printed on the package.

The amount is closer to 129.

I write “closer to” for good reason. Besides the problems of counting cals inherent in the Atwater system, research shows that people assimilate calories from the same food a bit differently. In fact, even the way you chew affects calorie assimilation. The more you chew your food, the greater the rate of digestion. More digestion means more calories absorbed.

The same is true for food preparation: the more preparation, the more absorption.

 Harvard professors and co-authors Richard Wrangham and Rachael Carmody clarify this in “Why most food labels are wrong about calories,” published by The Conversation in January of 2015. “If you eat a starchy food raw, up to half the starch grains pass through the small intestine entirely undigested . . . . Even among cooked foods [though], digestibility varies. Starch becomes more resistant to digestion when it is allowed to cool and sit after being cooked, because it crystallizes into structures that digestive enzymes cannot easily break down. So stale foods like day-old cooked spaghetti, or cold toast, will give you fewer calories than the same foods eaten piping hot, even though technically they contain the same amount of stored energy.”

To make counting calories even more of a crapshoot, the FDA allows the food processors a 20-percent margin of error before finding them in error. They also require food labels to list the percentage of key nutrients using a 2,000 calorie total — the amount Calorie control.org gives as needed for a moderately active, 132-pound female to maintain her weight.

In a worst-case scenario, a 20-percent margin of error for such a female eating that amount daily creates a caloric surplus of 400. Over the course of a month, that could cause an unintentional weight gain of more than 3 pounds.

Despite all these factors that make counting calories an inexact science, it still makes sense for cyclists to do so, particularly in the winter months when you ride less and are prone to put on a few pounds. That’s because while counting cals is imprecise, it is also effective. The process of weighing and measuring your foods increases your awareness of how often and how much you’re eating, which makes you more likely to eat when you’re hungry and less likely to eat when you’re bored.

At least that’s the way it’s worked for those who have sought my help with weight control, as well as the overweight and obese subjects in the study published in the August 2008 issue of American Journal of Preventive Medicine who counted calories by keeping a food journal. Although all 1685 involved attended 20 weekly groups sessions to encourage calories restriction, exercise, and adherence to the DASH diet, those who also counted cals lost twice as much weight as those who didn’t.