Calorie Tallies on Nutrition Labels Are Probably Bullshit, Says Science

Have you been mindfully reading the nutrition labels on all the foodstuffs you plan on putting into your body, conscious, perhaps, of the CDC’s finding that women who read labels have a lower average BMI than women who abstain from label-reading? Well, congratulations — you’ve been had once again by the fickle arbiters of good health! The calorie counts on nutrition labels and restaurant menus are, according to several recent studies, probably just guesstimates, and pretty flimsy guesstimates at that.

Nutrition labels have been using the same calorie-guesstimating system that Wilbur Atwater devised around the turn of the 20th century, so it’s not too shocking to learn that scientists are beginning to weary of Atwater’s antiquated system, which doesn’t make considerations for foods that are high in fiber, for instance. That’s because foods that haven’t been processed, prepared, or have lots of fiber are really hard to digest, so a proportion of their calories remain “locked up” during digestion. Meanwhile, explains LiveScience’s Rachael Rettner, food that has been chopped, sauteed, mashed, pounded, or processed has already had some of its digestive stubbornness wrung out of it, meaning that it will slip through digestive tract with all the ease and grace of an Olympic diver down a waterslide (this is why you have to be within 20 yards of a tolerable bathroom after every visit to Burger King).

Atwater’s system also doesn’t account for all the greedy gut bacteria skimming calories from our meals, and it fails to factor in the energy the body requires to move a loaded potato skin through the lower intestines. Many of these discrepancies, scientists admit, are negligible, but some nutrition labels may be off by a margin of up to 50 percent. Atwater, for instance, bestows 170 calories on a whole serving of almonds, but almonds have all this pent up fat that they will just not let our digestive systems have, so a serving is actually more in the neighborhood of 130 calories. If you’re a tree dwelling rodent hoping to trim down for beach season, this news is especially encouraging.