Nutritional Pearls: A Look Into the Risks of Land-Animal Protein
Answer: Compared with those who "never" consumed processed meat, those who consumed more than 150 grams per week were 51% more likely to die of any cause, 84% more likely to die of cancer, 46% more likely to experience a major cardiovascular event of any kind, 62% more likely to have a heart attack and 56% more likely to have a stroke.
The Research
Earlier this year we shared with you a study funded by the beef industry that showed that those who consumed a Mediterranean-style diet that included 2.5 ounces of lean beef per day saw improved cholesterol scores over those following an "average American diet."
We noted at the time that this wasn't news: a Mediterranean-style diet allows up to 3.25 ounces of lean land-animal protein per day, on average, so all this study did was emphasize that yes, beef, a land-animal protein, can be part of a healthy diet.
Not news.
Today's research is not limited to beef. It looks at all land-animal protein: beef, veal, mutton, pork, and poultry, as well as processed meats, defined as "meat that had been salted, cured, or treated with preservatives and/or food additives.”1
This prospective study made use of data gathered for the PURE (Prospective Urban Rural Epidemiology) Study, which began recruitment in 2003. This analysis includes nearly 135,000 people from 21 low-, middle-, and high-income countries across 5 continents. Participants with known cardiovascular disease were excluded from this analysis.
At the start of the study, participants responded to detailed dietary questionnaires that had been designed specifically for their country of residence, and in some cases the region of their country, listing common as well as regional foods in local serving sizes. The participants indicated how often, from "never" to "more than 6 times per day" they consumed each food.
The authors then standardized the participants' meat intake by multiplying the local portion size by frequency of consumption and converting to an average of grams consumed per week. The percentage of calories consumed in the form of land-animal proteins was then adjusted to a standard of 1000 calories per day to account for varying total caloric intake.
Bearing in mind that meat is a comparatively expensive food item, in their analysis the authors also considered participants' education level as well as comparative wealth, calculated by identifying household possessions such as electricity, car, computer, television, phone, and other material goods and conducting a components analysis to create a wealth index.
Along with education and wealth index, the authors also considered age, sex, location, smoking status, physical activity, diabetes status, whether the participant took blood pressure-lowering medication, their total caloric intake, and intake of fruits, vegetables, dairy products, fish/shellfish, total fiber, refined grains, and legumes.
The authors looked for a link between land-animal protein intake and death from any cause, death from cardiovascular disease, or death from cancer, as well as experiencing a major cardiovascular event, stroke, or heart failure.
The Results
In nearly 135,000 people followed over an average of 9.5 years, when comparing those who consumed the most red meat with those who did not eat red meat, the authors found no association between higher consumption of unprocessed red meat and any of the aforementioned conditions.
The same held true for poultry consumption, but processed meat was another matter entirely.
Compared with those who "never" consumed processed meat (that is, averaging 0 grams per week), those who consumed more than 150 grams per week were 51% more likely to die of any cause, 84% more likely to die of cancer, 46% more likely to experience a major cardiovascular event of any kind, 62% more likely to have a heart attack and 56% more likely to have a stroke.
What’s the Take Home?
150 grams is about 5.3 ounces. That's like having sausage or bacon every day at breakfast or eating a daily sandwich made with lunchmeats full of nitrates.
While no prospective study can prove causality alone, this adds to our understanding of the risks of processed meats. Save the bacon and sausage for an occasional treat, make your sandwiches with whole-grain bread, and use a small amount of leftover pork tenderloin, chicken breast or thigh, or lean beef. Pile that sandwich high with veggies, and you'll easily be adding at least 2 points to your Mediterranean Diet score.
Reference:
- Iqbal R, Dehghan M, Mente A, et al. Associations of unprocessed and processed meat intake with mortality and cardiovascular disease in 21 countries [Prospective Urban Rural Epidemiology (PURE) Study]: a prospective cohort study. Am J Clin Nutr. 2021;114(3):1049-1058. doi:10.1093/ajcn/nqaa448