There’s new evidence that links consumption of red meat (beef, pork and lamb) to your risk of colorectal cancer, according to the American Institute for Cancer Research.

The study’s expert panel issued a recommendation to limit consumption of red meat to no more than 18 oz. (cooked) per week and to avoid processed meats.

Many Americans eat far greater amounts of red meat per week. Consider someone who frequently chooses eggs with two sausage links (2 oz.) for breakfast, a quarter-pound hamburger (4 oz.) for lunch or a pork chop (6 oz.) for dinner. He’ll likely exceed the recommended 18 oz.

Every 3.5 oz. (100 g) of red meat eaten per day increases risk for colorectal cancer by 30%. Processed red meat (ham, sausage, bacon and cold cuts) raises risk by 42% for every 3.5 oz. eaten daily.

If you eat lunch or dinner at restaurants several times a week, it becomes even more difficult to keep consumption in check. Today, many restaurants offer 9- to 12-oz. servings of steak or roast beef and often compete for business by inflating portion sizes.

Cancer experts are asking Americans to assess the amount of red meat they typically eat, substitute poultry or fish more often, or increase the number of meatless meals consumed in a given week.

“The meat-and-potatoes mindset is slowly killing us,” says registered dietitian Karen Collins, the institute’s nutrition adviser. “We need to break ourselves of the notion that we need a hunk of red meat at every meal.”

Some Americans, however, are just a few ounces over the recommended weekly amount, she says. They can start lowering their cancer risk by substituting a hearty vegetable chili and salad for a hamburger at lunchtime, or preparing poultry or fish instead of a steak dinner two nights a week.

The AICR is not calling for the elimination of meat from U.S. diets. Instead, recognize that cutting back every week is an important cancer-protective step.

As for processed meat, AICR experts say it’s OK to indulge on special occasions—a ham at Easter, a hot dog at a ballgame—but making it part of your everyday diet is not a good idea.

According to government statistics, a gradual shift away from red meat has been under way in the United States for decades. The U.S. Department of Agriculture’s Economic Research Service reports  the average American’s annual consumption of beef has decreased by nearly 14 pounds (224 oz.) since 1970.

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