Gather round, folks, cause I’m gonna tell you a story.
Once upon a time- around 1890 actually- a scientist named Wilbur Atwater got the bright idea of putting food into a special machine, burning it and measuring the amount of heat it produced. The machine was called a calorimeter, and old Wilbur decided to call the energy produced by burning the food into ash “calories”. Thus he was able to figure how many calories were contained in just about any food you could think of.
Shortly afterwards, scientists applied the same concept to exercise. Using a few calculations, they soon figured out how many calories were “burned” doing everything from sleeping to cross-country skiing.
Within no time, an idea was born: weight gain happened when a person took in more calories than he burned up. The body, it was reasoned, behaves like a calorimeter. Put in calories (from food) use up calories (from living, exercising, digesting, etc) and look at your balance sheet. If more is coming in than going out, you gain weight. If more goes out than came in, you lose. Simple. Especially if the body behaved like a calorimeter.
But it doesn’t.
The people who sell empty, useless, nutritionally dead calories- sugar anyone? - love the calorie theory. According to them, since weight loss is only a matter of eating less calories, sugar is perfectly acceptable. Just don’t eat so many darn calories and you won’t get fat. If you do, says the sugar industry, don’t blame us. Sugar doesn’t cause weight gain, as long as you don’t eat more calories than you “burn”.
‘Course that ignores all the other things that sugar does besides provide (empty) calories: like raise blood sugar, depress the immune system, rob the body of calcium and use up mineral stores. But that’s another story.
Then there’s one other itty bitty problem: the body doesn’t behave like a calorimeter. It behaves like a chemistry lab.
Here’s an example: Eat a bar that’s 100 calories of sugar. Your blood sugar jumps up. The pancreas responds with a big shot of insulin, whose job it is to bring blood sugar down. In some people it doesn’t do such a great job, leaving them with high blood sugar and high insulin, both risk factors for heart disease. In others it does the job OK, but the sugar winds up in the fat cells. Either way, you lose. And we’re not talking about losing fat!
On the other hand, let’s say you eat a bar that’s 100 calories of protein, fat and fiber. The protein provides nutrients necessary for the building of the body’s architecture- bones, muscles, enzymes, neurotransmitters. It also makes you feel full so you’re less likely to overeat. The fiber slows the entrance of sugar into the bloodstream and also helps protect against cancer. The fat provides important building blocks for cell membranes and hormones. Protein has only a mild effect on blood sugar and insulin, and neither fiber nor fat have any effect at all. While both bars are equal from a calorie point of view, they are anything but equal from the point of view of hormones, fat storage and health.
The effect of different sources of calories on blood sugar and hormones like insulin is one of the most important concepts in nutrition, and one which dieticians still haven’t figured out
The bottom line: Eat foods that have the least impact on blood sugar- fiber, for example, and fat, along with green leafy vegetables, low sugar fruit and plenty of protein, all of which provide nutrients, building blocks and health benefits. Sugar on the other hand provides none of those, and will instead keep you on the blood sugar roller coaster that inevitably leads to health problems such as obesity.
So if you’re looking only at calories, you’re missing the fine print. Take two typical “low carb bars. While both have about 200 calories, Bar One has only 1 measly gram of fiber, 14 grams of protein, and 20 grams of sugar alcohols. Bar Two, on the other hand, has a whopping 10 grams of fiber, 19 grams of protein and a mere 4 grams of sugar alcohols, a sweetener which usually does not have a significant impact on blood sugar or insulin.
That’s the fine print that’s missing if you only pay attention to calories. Calories do matter- but they’re very far from the whole story.
Remember, God is in the details- or in this case, in the fine print.
Jonny Bowden, PhD, CNS is the author of the Poliquin Manual for Nutrition. He's a board certified nutritionist, a nationally known expert on weight loss, health and nutrition, and the best-selling author of 8 books including “The 150 Healthiest Foods on Earth”. Visit him at www.jonnybowden.com