Some evidence suggests that protein-rich meals turn up the (body) heat, although most studies on the issue are small and from decades ago. In one landmark study published in 2002, for instance, researchers from Arizona State University asked 10 young women to eat either high-protein or high-carbohydrate meals for one day and took various measurements, including body temperature. Then, either four or eight weeks later, the women came back to the lab and ate the other meal option. The women’s body temperatures were nearly 60 per cent higher, on average, after eating the more protein-heavy dinner than they were after eating the carbohydrate-rich dinner. Other small studies have suggested that the same thing happens in men.
Protein increases body temperature because your body must do more work — meaning exert more energy — to digest it, and this work also releases heat, said Marie-Pierre St-Onge, an associate professor of nutritional medicine at the Columbia University Vagelos College of Physicians and Surgeons.
That’s in part because protein is more difficult to break down than carbs or fats. Protein digestion is “energetically expensive,” said Stuart Phillips, a kinesiologist and director of the McMaster Centre for Nutrition, Exercise and Health Research at McMaster University in Hamilton, Ontario.
Our bodies use the proteins we eat to generate new proteins, too — and this process also produces heat, Layman said.
After you eat at least 30 grams of protein, for instance, your body starts to make its own muscle proteins, which “is a very energy expensive process,” Layman explained. “That will increase heat expenditure in the body,” meaning that it will make you warm.
Since so much of the energy from high-protein meals is quickly used by the body, a person burns three to four times as many calories after eating protein compared with eating carbohydrates or fat, Layman said. In one small study published in 1999, researchers found that when eight women followed a diet high in protein for one day, they burned an average of 87 more calories than when they followed a diet high in fat.
One theory with only limited evidence is that we may be warmed more by meals we enjoy than those we don’t. In a small study published in 1985, eight women consumed either a palatable meal of cheese fondue, spaghetti with meatballs, a chocolate éclair and a soda, or they consumed the same foods blended and formed into a flavourless, dry biscuit. The next day, the women switched and consumed the other meal. The researchers found that the women’s bodies released about half as much heat after eating the tasteless biscuit compared with the delicious feast. Though this study does not seem to have been repeated since.
Still, meat sweats may be a stretch
Although protein does warm the body, experts aren’t convinced that eating lots of meat — even if delicious — will cause a person to sweat much, if at all.
“Meat sweats are not a thing,” Layman said. In the studies that have been done, he added, “no one has ever reported sweating.”
Meat may not induce sweating because, although protein does increase body temperature more than other macronutrients do, the relative temperature increase is quite small. The body temperatures of the women in the 2002 study were only 0.2 to 0.3 degrees higher, on average, after following the protein-heavy diet.
St-Onge, who was not even familiar with the term “meat sweats,” said it’s possible that a person might slightly perspire after eating lots of meat, but “I don’t think that people would start sweating profusely.”
However, if you gorge on meat while you’re already feeling hot, that could tip you over the edge, she added. “If you have a high-meat meal in the middle of summer in midtown Manhattan, outside, and it’s like 90 degrees, yes, you will sweat,” she said.
This article originally appeared in The New York Times.
Written by: Melinda Wenner Moyer
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