Does red meat cause cancer? Here’s what the science says

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Q: I’ve heard eating a lot of processed meats like hot dogs or sausages causes cancer, but what about red meat in general like hamburgers and steaks? Should I cut down on these too?

A: I can’t tell you with full certainty that eating red meat will increase your cancer risk – only that the data is concerning enough that the benefits of frequently eating red meat don’t outweigh the risks.

Red meat consumption in America varies widely. A 2023 analysis of National Health and Nutrition Examination Survey data found that about 45% of the population ate zero beef on any given day, whereas 12% account for half of the total beef consumed by the entire country.

You don’t need to eliminate red meat, but I do advise my patients to limit it: Aim for no more than three servings a week (a serving is around 3 to 4 ounces), because that’s the range most studies indicate is less likely associated with cancer. To put this in perspective, if you eat one 12-ounce steak for dinner, you could get close to that limit in a single meal.

And to be clear: I’m talking about red meat in general like steaks and hamburgers. With processed red meats like in hot dogs or sausages, where the health risk is even greater, I advise cutting down as much as possible.

The benefit of marinating red meat

If you are going to eat red meat, try this science-backed trick to reduce potential carcinogens: Marinate it one hour before cooking.

Here’s why: In 2008, researchers at Kansas State University marinated beef round steaks in three marinades prepared with antioxidant-containing spices. Then they grilled them. Interestingly, a Caribbean-inspired marinade, with thyme, red and black pepper, allspice, rosemary and chives, lowered carcinogens by the highest amount – 88%. But all three marinades decreased carcinogens.

The researchers suspected this occurs because the marinade was seared instead of the meat directly, which could theoretically reduce the formation of carcinogens. It also may be because the marinades contained two or more spices from the mint family, which are rich in beneficial plant compounds called polyphenols.

How to cook healthier red meats

Specific carcinogens can spontaneously form when meats are cooked at high temperatures, said Mariana Stern, a cancer epidemiologist at the Keck School of Medicine of the University of Southern California.

A few simple tips can help:

1. Avoiding charring, smoking or cooking meats at very high temperatures, like with grilling or pan-searing. Try to keep the heat under 400 degrees Fahrenheit and minimize direct exposure of meat to an open flame. Slow-cooking meat is a great option. Make sure that the meat reaches a safe internal temperature to prevent foodborne illnesses (145 to 165 degrees Fahrenheit depending on meat type), Stern said.

2. Marinate your meat beforehand. The 2008 study analyzed wet marinades made with a combination of soybean oil, water, vinegar and spices. But other studies have found that marinades with honey can also effectively reduce carcinogen formation when cooking meats.

3. Harmful chemicals often concentrate in meat drippings, including those used to make gravy. Use a drip pan rather than letting drippings encase the meat.

4. Flip your meat often. This can reduce chemical formation as opposed to just leaving it on the heat source without turning it over.

5. Lastly, I advise picking leaner cuts of meat and eating grass-fed beef, which has higher quantities of omega-3 fatty acids, which are unsaturated fats, when possible. There’s no data to suggest these will directly influence your cancer risk, but they may be better for your heart. Leaner cuts of meats have long been recommended due to the risks associated with higher saturated fat content and increased cholesterol.

What should I eat instead of red meat?

Perhaps what’s even more important than cutting out red meat is what you choose to replace it with.

“While no diet can eliminate cancer risk entirely, limiting red meat and emphasizing a whole-food, plant-based diet can help reduce it,” said Lindsey Wohlford, a registered dietitian at the University of Texas MD Anderson Cancer Center.

She recommends that people struggling to make a change focus on adding healthy foods rather than eliminating favourites.

Focus your meals on plant-based proteins like lentils, tofu and beans, as well as whole grains, fruits and vegetables. These foods are high in fiber and carry numerous other health benefits, including – but not limited to – lowering cancer risk.

The science on red meat and cancer

So how sure are we that red meat causes cancer? Sure enough that scientists are concerned – especially for people who eat red meat frequently.

In the 1970s, epidemiological studies found a significant correlation between meat intake and colon cancer. These observational studies did not prove causation, but subsequent research attempted more rigorous methods, including the famous Nurses’ Health Study and Health Professionals Follow-up Study. Both demonstrated strong associations between colon cancer and red meat consumption.

But it’s hard to definitively conclude red meat is the direct cause. Although researchers took lifestyle factors like exercise and diet into consideration, there may be other variables that could influence these results.

“I think it is hard to isolate and focus on single risk factors or banking on a single smoking gun,” said Y. Nancy You, a colorectal surgical oncologist at the University of Texas MD Anderson Center.

Nonetheless, taken together, these – and roughly 800 other studies – helped form the basis of the 2015 report by the International Agency for Research on Cancer classifying red meat as a 2A carcinogen, meaning “probably causes cancer.”

Since then, much more data have emerged. We now have greater insight into possible mechanisms behind this link, including how chemicals introduced while cooking may drive precursors of colorectal cancer.

What I want my patients to know

Stern acknowledges that despite mounting evidence, there are many reasons people push back against the idea that red meat – not just processed meat – could be linked to cancer risk: Red meat has been an enjoyable staple of the American diet for generations and is often available cheaply.

“There is also some level of fatalism in the population, with some people having the perception that ‘everything causes cancer,'” Stern said. “Thus, why deprive themselves of something they may like, if in the end, everything is bad?”

What I think about most at the end of the day is this: Between 30 and 50% of cancers are preventable, and cancer cases continue to rise among younger adults. Red meat is just one of several possible lifestyle factors that we need to weigh. So talk to your doctor about your health history to get an idea of your personal risk.