Why the Calorie Is Broken (arstechnica.com)

An anonymous reader writes: Nutrition is a subject for which everybody should understand the basics. Unfortunately, this is hard. Not only is there a ton of conflicting research about how to properly fuel your body, there's a multi-billion-dollar industry with financial incentive to muddy the waters. Further, one of the most basic concepts for how we evaluate food — the calorie — is incredibly imprecise. "Wilbur Atwater, a Department of Agriculture scientist, began by measuring the calories contained in more than 4,000 foods. Then he fed those foods to volunteers and collected their faeces, which he incinerated in a bomb calorimeter. After subtracting the energy measured in the faeces from that in the food, he arrived at the Atwater values, numbers that represent the available energy in each gram of protein, carbohydrate and fat. These century-old figures remain the basis for today's standards."

In addition to the measuring system being outdated, the amount of calories taken from a meal can vary from person to person. Differences in metabolism and digestive efficiency add sizable error bars. Then there are issues with serving sizes and preparation methods. Research is now underway to find a better measure of food intake than the calorie. One possibility for the future is mapping your internal chemistry and having it analyzed with a massive database to see what foods work best for you. Another may involve tweaking your gut microbiome to change how you extract energy from certain foods.

Comments

Re:Not the Calories fault?

[Anonymous Coward]

Yeah, the Calorie is pretty well defined. 1 Calorie = 1kcal = 1000 calories, with 1 calorie defined as the amount of energy it takes to heat up 1 ml of water 1 degree C. If that's broken, then so is the joule. Now if the number on the side of the box is wrong, that's believable. If they're consuming more then the serving size without realizing it, that's believable (seriously, this small package contains 2.5 servings?). Different peoples digestive systems operate at different efficiencies, thus different people get a different amount of energy out of the food, that's believable. And it's well known the amount of energy you burn depends on your amount of activity and the amount of muscle you have which means that wearing a fitbit to track your energy expenditure is almost certainly worthless. Considering all those things on why losing weight isn't so easy to put into a simple mathematical formula still doesn't imply that the calorie is broken. It does it's job of measuring energy just fine.

Re:Stupid headline

[CastrTroy]

I agree. The Calorie is a useful measurement. If you monitor your health by tracking Calories eaten, weight, and Calories expended then you should be able to control your weight. If your weight is going up, you have few options, reduce your Calorie intake, or increase your calorie expenditure, or some combination of the two. Maybe the numbers on the packaging don't work for you, and you actually get more energy out of the foods you are are eating than what's reported on the label. The fact still holds that if you eat less of the foods then you will be getting fewer calories, and you will be able to lose weight. If you are somehow overestimating how many Calories you are using with exercise and other baseline activities, then you simply need to increase the amount of exercise, and you will burn more calories. The important thing here is to monitor what you are eating, and how much exercise you are doing, and adjust the inputs until you get the desired output. If you aren't monitoring anything then there's no way to tell if you are headed in the right direction