Why Is It Hard for Humans to Eat Raw Meat?

Steak tartare

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The primal diet and other raw meat diets have been around for years. The question is, could humans ever eat raw meat? Although it's possible, it doesn't mean it's safe or healthy.

Can Humans Eat Raw Meat?

Raw meat consumption dates back to the Paleolithic era, but it's hard to tell how frequent it was among early humans. According to a research paper published in the March-April 2016 issue of American Scientist, cooking makes food easier to chew and digest, allowing your body to get more nutrients from it. This could explain why the biggest increase in brain size was recorded when early humans started to cook their food.

As the researchers note, modern humans are adapted to cooked foods and may have difficulty reproducing while on a raw food diet. A study cited in the above review has found that one-third of women of reproductive age didn't have menstrual periods, which may be due to their eating habits. Subjects were only eating raw foods and probably had low body weight, says the American Scientist.

A more recent study published in the Journal of Food Quality in August 2019 suggests that cooking any type of meat at 212 degrees Fahrenheit may improve its digestibility. The meat is even easier to digest when cooked along with mushrooms and other vegetables containing proteolytic enzymes that help break down protein, according to Winchester Hospital. Rice, potatoes and other high-carb foods, on the other hand, may reduce meat digestibility.

An article published in the March 2016 issue of Sapiens, a publication of the Wenner-Gren Foundation for Anthropological Research, states that human teeth cannot break down raw meat properly because of their flat surface. Early humans were most likely chopping the meat with stone tools to make it edible. Scientists say that humans can chew raw meat as long as it's cut into small pieces.

Raw Meat Diet Safety Concerns

The above findings indicate that a raw meat diet is feasible. In fact, some studies suggest that raw meat is slightly more nutritious than cooked meat.

For example, a March 2014 study featured in Meat Science has found that roasting and grilling did not affect vitamin B12 levels in beef. Frying, on the other hand, decreased the vitamin B12 content of raw beef by more than one-third. Even so, it doesn't mean that switching to a raw meat diet is safe or healthy.

Raw meat can be contaminated with bacteria and cause food poisoning. Trichinellosis, for instance, is a roundworm infection that may result from eating undercooked meat, warns the Mayo Clinic. Its symptoms include nausea and vomiting, digestive distress, fever, diarrhea, chills and more.

According to the U.S. Department of Health and Human Services, raw meat may also contain Salmonella, E. coli and other parasites. The only way to destroy these microorganisms is to cook the meat thoroughly. The USDA Food Safety and Inspection Service recommends cooking ground meats at 160 F or higher, poultry at 165 F and beef, veal, pork or lamb at 145 F to kill pathogens. Ham should be cooked at 145 F.

A list of meats you can eat raw may include steak tartare, ground beef ceviche (Carne Apache), beef carpaccio and mett, a German dish consisting of minced pork spread. But these popular dishes are not always safe. Steak tartare, for example, is usually served in high-end restaurants that adhere to the highest safety standards. Even so, there is still a small risk of bacterial contamination, according to McGill University.