April 6, 2015 | 2 minute read

Q: Why do nutrition recommendations talk about limiting red? Can’t I keep my saturated fat low by simply choosing lean cuts?

A: When eating red meat (beef, pork or lamb), choosing lean cuts is important in order to limit saturated fat and avoid excess calories. But eating too much of any red meat – more than 18 ounces cooked, weekly – increases risk for colorectal cancer. Red meats that are processed – such as bacon, hot dogs and sausage – are also available in leaner forms, yet even small amounts of these meats, eaten regularly, lead to higher risk for colorectal cancer. Processed meats are also consistently linked to increased risk of heart disease and type 2 diabetes.

There are several potential theories as to why red meat may link to increased risk of these chronic diseases. Red meat (especially beef and lamb) is high in a form of iron called heme iron. Heme iron is also found in smaller amounts in chicken and fish. Higher heme iron content may partly explain links between excess red meat and risk of colon cancer, since it seems to promote formation of compounds that can damage intestinal cells. Some large population studies link higher consumption of heme iron and heme iron from red meat with increased risk of heart disease and type 2 diabetes, respectively.

Emerging research also suggests that bacteria in the gut may play a role. It may convert compounds in red meat to substances that promote atherosclerosis (“hardening of the arteries”) and/or cause less healthful types of bacteria in the intestinal tract to flourish.

Since unprocessed red meat in excess amounts is linked to colon cancer and may pose other health risks, choose lean cuts of fresh meat and also limit amounts to no more than 18 ounces per week. And be sure to save processed meats for special occasions.