That piece of sausage you're about to enjoy? You may want to put it down for something healthier.
New research found an association between eating even small amounts of processed meats, 150 grams (a little over 5 ounces) per week, and a higher risk of major heart disease and death.
But not all meat is bad: The study, which includes data from 21 countries, also found that eating up to 250 grams (just under 9 ounces) per week of unprocessed meat, even red meat, was neutral in terms of cardiovascular disease.
Why are processed meats, such as hot dogs, cold cuts, and bacon, considered to be so unhealthy?
"We believe this might be the result of food preservatives, food additives, and color because if you compare, cholesterol and saturated fat in unprocessed and also processed are very similar, the difference is in food additives and color and nitrate," said study author Mahshid Dehghan, an investigator at the Population Health Research Institute of McMaster University and Hamilton Health Sciences in Ontario, Canada.
Most past evidence on meat intake and health outcomes comes from studies that were done in North America, Europe, and Japan. The amount and type of meat consumed in those areas differs from some other parts of the world, including South Asia and Africa, according to the study.
Enter PURE, a long-term study that is tracking dietary habits and health outcomes of more than 164,000 people in countries that include those with low, middle, and high incomes. The study launched in 2003. It uses food frequency questionnaires. Researchers also collected other health data.
In the study, unprocessed red meat was beef, lamb, veal, and pork. Poultry included all birds. Processed meat was any meat that had been salted, cured, or treated with food preservatives or additives.
The increased risk was incurred with even a small amount of processed meat, according to the study.
"I would say it's about two servings per week. A medium-sized sausage is about 75 grams. Having two sausages per week is associated with this amount of increasing risk," Dehghan said. "The message of our study is really limiting consumption, very limited amount of once in a while, not very frequent consumption."
Despite the neutral finding on unprocessed meat, a news release sent with the study cautioned that red meat is a major source of medium- and long-chain saturated fatty acids, which may up the risk of cardiovascular disease.
The association between diet and disease isn't linear, but is U-shaped, Dehghan said, with both insufficient and excessive amounts of certain foods being bad for you. Meat can be a good source of protein, iron and, other essential nutrients, Dehghan explained, but consuming an excessive amount can add other risks.
The authors said more research is needed to improve understanding about meat consumption and health outcomes. For example, what participants with lower meat intake are eating instead may have an impact on health outcomes.
The study was published March 31 in the American Journal of Clinical Nutrition.
"When you look at comparing intake in countries who consume very little meat versus countries who do, it's hard to draw conclusions," said Connie Diekman, a food and nutrition consultant in St. Louis. "As a registered dietitian, my best message in looking at this study is let's put this in with the bigger body of research where we know that the amount of meat we consume needs to be reduced versus the amount of plant foods."
Diekman noted that limitations of the PURE study include that food frequency questionnaires can be inaccurate and that consumption varies a lot between countries.
"The study did point out when you look at those countries with higher consumption, you see more disease risk," Diekman said.
Foods that contain higher amounts of saturated fats, including some meats, should be consumed in moderation and within an overall eating plan where there are a lot of fruits, vegetables, whole grains, and low-fat dairy, she said. The body of evidence suggests that people should limit consuming processed meats.
"The bottom line when we look at animal foods, whether we're talking the raw meat, the processed meat, the dairy foods, the whole animal line, is we do have more saturated fat in those animal foods and they need to be consumed in moderate amounts," Diekman said.