NEW YORK – The idea that consuming a meat-heavy meal can cause people to perspire profusely has been around for decades.

Although it is unclear exactly when and where the term was coined, it was popularised in a 2001 episode of American sitcom Friends, when the character Joey Tribbiani ate an entire turkey, wiped his forehead and said: “Here come the meat sweats.”

In June 2022, fast-food chain Arby’s teamed up with Old Spice to sell a “Meat Sweat Defense” kit, which included a custom roast beef sweatsuit, gym towel, sweatband and a can of deodorant spray.

But is this just clever marketing or will scarfing one too many roast beef sandwiches really make you sweat like you just ran a marathon?

Research suggests that eating protein does raise body temperature more than eating carbohydrates or fats.

Yet, there is little evidence to suggest that this increase is large enough to incite sweating, said Dr Donald Layman, professor emeritus of food science and human nutrition who studies protein metabolism at the University of Illinois Urbana-Champaign.

So, the phenomenon may be rooted more in myth than reality. Here is what the experts say.

Protein warms the body

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 Associate Professor Marie-Pierre St-Onge of nutritional medicine at the Columbia University Vagelos College of Physicians and Surgeons.

That is in part because protein is more difficult to break down than carbs or fats.

Protein digestion is “energetically expensive”, said kinesiologist Stuart Phillips, who is also director of the McMaster Centre for Nutrition, Exercise and Health Research at McMaster University in Hamilton, Ontario.

Bodies use the proteins people eat to generate new proteins too – and this process also produces heat, Dr Layman said.

After you eat at least 30g of protein, for instance, your body starts to make its own muscle proteins, which “is a very energy expensive process”, he said. “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, he added.

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 people may be warmed more by meals they enjoy than those they do not.

In a small study published in 1985, eight women consumed either a palatable meal of cheese fondue, spaghetti with meatballs, a chocolate eclair 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.

But meat sweats may be a stretch

Although protein does warm the body, experts are not 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,” Dr 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.

Prof St-Onge, who was not even familiar with the term “meat sweats”, said it is 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 are 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 (Fahrenheit), yes, you will sweat,” she said. NYTIMES