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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In addition to the measuring system being outdated, the amount of calories taken from a meal can vary from person to person.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.

1 of 425 comments (clear)

  1. Re:I guess it's easier... by Forgefather · · Score: 5, Interesting

    I would recommend reading the article. For once they actually linked to an in depth discussion of the topic and the author cites a lot of useful information. For inctance, there is wild variance in calories based on whether or not the food you eat is completely cooked. Large pieces of meat can be potentially hundreds of less usable calories if prepared rare instead of well done.

    It is this evidence that the article uses to criticize the calorie because a calorie is a measure of the absolute value of energy in the food you eat not the measurement of what the usable amount of energy is. Furthermore the article delves into how those calorie measurements are taken, and cites several pieces of evidence that those calorie amounts are highly inaccurate.

    The article also disuses the role that gut bacteria play in our digestion, citing an example where a mother had gut bacteria transplanted from here obese daughter and gained 40 lbs without any change to diet an exercise. Thus diet and exercise are not the only influences of what we gain and how much. The article is littered with such evidence.

    It is not just as simple as the food pyramid which, btw has been a broken model since its inception. Protein is supposed to occupy the lowest rung not carbohydrates and this has been well understood for years. Any doctor should be able to tell you that.

    In the end I do understand where you are coming from. After all I am someone that lost 60+ lbs just by counting calories, but there are a lot of things that I could verify within the article based on my experiences. Such as continued unexplained weight loss even when I seemingly exceeded the maximum calories per day that I should have been eating. The article is definitely worth your time to read and even if you disagree with the assertion that the calorie is a broken method of measurement there is still a lot of useful information present.

    --
    "There are lies, there are damn lies, and there are statistics"