The weird truth about calories and why food labels get them so wrong

WHEN you are navigating nan analyzable world of nutrition, nan calorie feels mercifully simple. A straightforward measurement of nan power successful our food, calories beryllium astatine nan bosom of accepted weight power advice. Consume excessively many, aliases neglect to pain enough, and you will put connected weight. Want to slim down? Eat little and move more. As nan saying goes, “a calorie is simply a calorie is simply a calorie”. Dig a small deeper, however, and you find it isn’t that simple.

This thought of nan assemblage arsenic a furnace and nutrient arsenic its substance was popularised by Wilbur Atwater successful nan 19th century. He deduced that location are 3 main components, aliases macronutrients, pinch which we tin cipher nan calorie contented of immoderate food: protein and carbohydrates incorporate 4 calories per gram, while fats incorporate 9. Combine these and nan consequence informs nan calorie contented connected nutrient labels everywhere.

But deliberation astir really nutrient is consumed and you deed your first problem. Take an orange, says Giles Yeo, a geneticist astatine nan University of Cambridge and writer of Why Calories Don’t Count. An orangish is chiefly carbohydrate, aliases sugar. “When you portion orangish juice, your assemblage will sorb nan sweetener [quickly] because location is nary digestion required,” says Yeo. Eat orangish segments, however, and it takes power for nan digestive strategy to activity connected nan fibre and extract nan sugar. “Physiologically, your assemblage does wholly different things pinch it, pinch precisely nan aforesaid calorie hit,” says Yeo.

Orange juice causes a much accelerated spike successful humor sweetener levels than nan orangish segments, for example, and regular surges successful humor sweetener …