Red meat in a Mediterranean-style Diet

It's getting better, but we still have patients who believe that red meat is bad for them, and that if they want to eat healthier, they have to give up all red meat.

The truth is that processed meats like bologna, bacon, and sausage are far greater risks to your health than lean, unprocessed red meats like beef (from cows), lamb, and pork (not 'the other white meat'). Further, those risks appear to be associated more with the nitrites used to process the meats rather than any inherent quality of the meat itself other than their higher levels of saturated fats.

Mediterranean Diet guidelines state that to receive a point on your Mediterranean Diet score you should consume less than 4 ounces of meat (including both red and white meats) per day, on average (3.25 ounces if you are a woman). The question some researchers have is just how much red meat is allowed in order to reap the cardiovascular benefits of a Mediterranean Diet (Am J Clin Nutr 2018;108:33-40).

The authors recruited 41 clinically overweight or obese men and women to participate in a feeding study. Before the start of the study the participants responded to a dietary questionnaire and kept a 3-day food log to measure their typical diets' adherence to a standardized Mediterranean Diet scoring system. For this scoring system, adhering to a perfect Mediterranean-style diet would give you 14 points, but all participants in this study got no more than a score of 4 on that Mediterranean Diet scoring system.

For this study, the participants following one of two assigned diets for 5 weeks, then returned to their usual diet for 4 weeks, then followed the other assigned diet. The two different diets were both Mediterranean-style diets, with the only difference being that during one five-week period the participants followed a "control" Mediterrean-style diet, which included an average of about 200 grams of unprocessed, lean red meat (read: beef or pork) per week, or a "Med-Red" diet, which was also a Mediterranean-style diet, but included about 500 grams of unprocessed, lean red meat per week. Which type of Mediterranean Diet the participants followed first was determined randomly.

What's unusual about this study is that all foods were provided to the participants for each of the two 5-week Mediterranean Diet periods. Further, the meals provided to the participants were not only designed to ensure a very high degree of adherence to a Mediterranean-style diet (a score of at least 13 of 14 for the Mediterranean Diet scoring system used), but were also designed to maintain each participants' body weight given their usual caloric intake and exercise levels.

Similarly, the participants' diets were also designed to keep their macronutrient intake (protein, saturated fat, monounsaturated and polyunsaturated fats) largely identical during the two Mediterranean-style diet periods, regardless of how much meat the participants were assigned to consume.

The authors subjected each participant to a battery of blood tests just before starting each Mediterranean Diet period and during the last week of each Mediterranean Diet period, then compared results for each participant between the standard Mediterranean Diet and the "Med-Red" diet.

After taking into account age, gender, and Body Mass Index at each point, the authors note that those following a Med-Redn diet reduced their BMI more than those following a Mediterranean Diet, although that difference was not clinically significant after each participant had followed both diets.

Similarly, both Mediterranean-style diets improved total cholesterol scores, triglycerides, glucose, insulin, and C-reactive protein scores about the same amount, although the Med-Red diet seemed to reduce LDL cholesterol by slightly more than the standard Mediterranean Diet.

What this means for you

The authors note that the standard advice has been to adopt a Mediterranean-style diet with a fairly low intake of red meat, like the control Mediterranean-style diet in this study. However, in this study the authors found that a higher intake of unprocessed red meat, closer to the typical amount of red meat consumed by Americans, conferred benefits that were similar to a diet lower in unprocessed red meat. This suggests that if you would rather not drastically cut your intake of red meat or avoid it altogether, choosing leaner red meats might be a positive step toward cardiovascular health in the context of an overall Mediterranean-Style Diet.

One caution attached to this study is that it was funded in part by the Beef Checkoff and the Pork Checkoff (marketing groups for beef and pork, respectively), and at least one of the authors has received grant funding or travel reimbursements from the Beef Checkoff, the Pork Checkoff, the National Dairy Council, the North Dakota Beef Commission, and the American Egg Board - Egg Nutrition Center.

Even so, their results are consistent with other studies of lean, unprocessed red meat.

First posted: October 3, 2018