The story on meat and colon cancer can seem very confusing. One minute you hear a news report saying that meat causes colon cancer, the next you may hear that meat is fine. But if we consider the dozens of studies on this topic, a "big picture" emerges: Eating meat is linked with colon cancer risk, but what kind, how much, and how the meat is prepared are important parts of the story.
Type of Meat and Colon Cancer Risk
Different types of meat appear to have different effects on the colon. Some types of meat cause more damage, damage that can lead to cancer development, to the cells in the colon than other types of meat. And when it comes colon cancer risk, fresh is best.
This means that in terms of colon cancer risk, freshly prepared chicken, other poultry, fish, lean beef, and pork are "safer" than processed meats. Processed means smoked, cured, and salted meats, such as hot dogs, sausages, salami, bologna, bratwurst, bacon, salt pork, cold cuts and lunch meat, ham, pastrami, pepperoni, smoked fish, corned beef, and jerky. It turns out that when processed, cancer-causing (carcinogenic) chemicals are created in meat. These chemicals, when eaten, increase colon cancer risk.
Meat Preparation, Cooking and Colon Cancer Risk
How meat is prepared and cooked also has an impact on how much the meat increases colon cancer risk. The higher the temperature at which the meat is cooked, and the more well-done the meat is, the more likely it is to increase colon cancer risk.
Just as with processing of meat, cooking meat at high temperatures until very well-done creates carcinogens (cancer-causing compounds). More well-done meat contains higher levels of carcinogens, called heterocyclic aromatic amines (HAAs) and polycyclic aromatic hydrocarbons (PAHs) than less well-done meat.
HAAs and PAHs are formed when the protein and/or fat in the meat gets very hot. Think of the black, char-grilled exterior that a piece of grilled meat can have. This is a source of carcinogens, the chemicals that can increase colon cancer risk.
How Much Meat is Too Much?
To put the "how much" question about meat and colon cancer risk into perspective, keep in mind:
- When studying diet and colon cancer, health experts have found that people regularly eating the most red meat have up to 50% greater colon cancer risk compared with people eating the least red meat.
- Eating more than 3-5 ounces of meat per day significantly increases the risk of death from any cause, including death due to colon cancer, other cancers, and heart disease.
- Eating more than an ounce and a half of processed meat per day, such as hot dogs and lunch meat, significantly increases the risk of death due to colon cancer, other cancers, and heart disease.
- A 3-ounce serving of meat is about the size of a deck of cards. Simply eating a roast beef sandwich for lunch and a burger or hot dog for dinner will put you over the daily limit for meat intake that research tells us will increase your risk of colon cancer, other cancers, heart disease, and death.
Meat in Moderation and Cooked Properly
If you enjoy meat, but want to keep your risk for colon cancer in check:
- Focus on Quality, Not Quantity. You don't need to skip meat altogether, as long as the rest of your diet is based around healthy, cancer-fighting foods such as vegetables, fruit, whole grains, legumes (beans and peas), nuts, and seeds. Enjoy good-quality, fresh meat in 3-ounce servings, 3-4 times per week.
- Cook Slow & Low. Even if two pieces of meat are cooked to the same "level of done-ness", the one that was cooked at a lower temperature for longer will contain fewer carcinogenic (cancer-causing) compounds than meat that is cooked very hot and fast.
- Raise the Flavor with Spices and Herbs. Marinade your meat in mixtures that contain spices and herbs such as rosemary, thyme, oregano, basil, fennel, or anything you enjoy. Believe it or not, marinating meat in spice and herb mixtures actually reduces the amount of carcinogens that are formed during cooking!
- Use the Right Tools. When grilling, use tongs to flip the meat rather than a fork. Piercing the meat causes fat and juices to drip onto the coals. This, in turn, causes the formation of carcinogens that coat the meat when smoke rises back up from the grill.
- Cook with Plants. You can heat up vegetables, fruit, or any other plant-based food as hot as you want. This does not create the hazardous compounds that are formed when meat is cooked. Try kabobs with plenty of vegetables on them.
As a final note, if you're looking for another reason to improve your meaty diet, consider the environment. By eating less meat, you'll improve the health of the planet too!
American Institute for Cancer Research. "Grilling and Cancer: Rating the Risk." Accessed September 29, 2009.
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