Have you ever taken heroin for a cough, or a tobacco enema for a cold? If you answered “yes,” please call 911. If you said “no,” that’s because these insane prescriptions of the 1800s have long since vanished.
Yet one theory from the same time period continues to dominate the nutrition world: all calories are equal. If you’ve ever found yourself counting calories to “be healthy,” you’re relying on the outdated science that, taken at face value, is about as likely to improve your health as blowing smoke up your ass.
A (very) brief history
The calorie was first introduced around 1820 by a Frenchman talking about heat engines. When it entered the English language in the 1860s, it was with a capital C and referred to the amount of heat needed to raise one kilogram of water from 0 to 1 degree Celsius. In the late 1800s, the US food industry adopted the Calorie as a unit for food energy, and by the mid-20th century, it was an indelible part of the nutrition landscape.
Having a soft spot for an old term is one thing, but this jumbled history as both a food energy unit and heat unit has caused problems for the way we think about nutrition. Rather than being a standardized, specific amount of energy, the calories that enter your body travel through a complex web of systems that treat them very differently, depending on their source.