Like salt, black pepper sits on almost every kitchen table or countertop in America. But while whole books have been written about sodium consumption and human health, black pepper and its compounds have garnered little attention from experts.
But pepper probably deserves more scrutiny. Some research has linked black pepper marinades to the elimination of heterocyclic amines, or HCAs, which are the cancer-causing chemicals that form when meat is charred or cooked at high temperatures. A group at Kansas State University found that mixing one gram of fine black pepper with 100 grams of ground beef—which works out to about a teaspoon of black pepper per half-pound of meat—almost completely eliminated the formation of HCAs during cooking.
While that much pepper may be too pungent for some, the study author says that mixing pepper with oregano, rosemary, and other herbs in the same spice-to-meat ratio should provide the same carcinogen-lowering benefits.
Pepper may also aid digestion. “There are a number of animal studies that indicate some potential benefit for the gastrointestinal tract,” says Keith Singletary, professor emeritus of nutrition at the University of Illinois, who wrote an overview on the research on pepper. (The paper was funded by the McCormick Science Institute, which studies the benefits of spices.) While the evidence isn’t always consistent, some of it suggests that black pepper may stimulate the secretion of digestive enzymes that help you feel full after a meal and ease food’s transit through the GI tract, Singletary says. “It may also enhance the absorption of some nutrients,” he adds.
In particular, experts have looked into the ability of piperine—the organic compound that gives black pepper its appealing piquancy—to increase the body’s absorption of curcumin and resveratrol. Curcumin is a chemical found in turmeric root, and there’s evidence linking it with numerous anti-inflammatory and antioxidant properties. Resveratrol, meanwhile, is a red wine compound that may lower a person’s risks for brain disorders, heart disease and type-2 diabetes.
While not all health experts are sold on these compounds’ benefits, most agree that curcumin and resveratrol have poor bioavailability—meaning they tend to pass through the human digestive system without being absorbed. This is where black pepper comes in. “We found that the addition of piperine significantly improved the bioavailability of resveratrol,” says Nihal Ahmad, a professor of dermatology at the University of Wisconsin School of Medicine and Public Health who has studied the effect piperine has on the body’s absorption of resveratrol.
Piperine seems to partially block a metabolic process known as glucuronidation, Ahmad says, which causes resveratrol to break apart before the gut can absorb it into the bloodstream. By interfering with this process, piperine may help the body take up more resveratrol. And some related studies have shown that piperine has a similar absorption-supporting effect on curcumin. (A number of commercial supplement makers already sell curcumin and resveratrol products that contain piperine.)
It would be grand if grinding a little black pepper onto your turmeric-spiced curry—the one you’re washing down with a glass of red wine—would unlock all of the purported health benefits of resveratrol and curcumin. But the research to date doesn’t support this. “Whether the amounts of black pepper used for culinary purposes have any health benefits—I think that’s unknown,” Singletary says. “A lot of the studies on spices have been in animals and cell cultures, and there aren’t a lot of human studies to back them up.”
Ahmad’s study, for example, involved feeding mice 10 mg of piperine per kilogram of bodyweight. A 125-pound human would need to swallow nearly two tablespoons of black pepper to get that same amount of piperine. Few of us would be willing (or able) to stomach that much pepper.
Taken in high doses as part of a supplement, piperine could even present some problems. “There’s the risk of absorbing things you don’t want in the body,” Ahmad says. The same digestive process that breaks down curcumin and turmeric before they can be taken up into the bloodstream also keeps certain unhealthy food components—including some hormones and chemicals—from being absorbed, he says.
Ahmad also says that, if you’re taking prescription drugs, it’s possible (though not proven) that swallowing heavy doses of piperine could interfere with the action of these medicines. These sorts of unintended consequences lead many doctors to warn against the risks of over-the-counter supplements.
Taken together, the evidence to date suggests that black pepper used the way most of us do—sprinkled or ground onto food—doesn’t pose any health risks. And it may offer some digestion or nutrient-absorption benefits. But even if it doesn’t, adding it to your meat marinade may provide some meaningful anti-cancer benefits.