June 13, 2018
New study finds Mediterranean-style eating pattern with lean, unprocessed red meat improves cardiovascular disease risk factors
WEST LAFAYETTE, Ind. — Adopting a Mediterranean-style eating pattern improves heart health, with or without reducing red meat intake, if the red meat consumed is lean and unprocessed, according to a Purdue University nutrition study.
“This study is important because it shows that red meat can be part of a heart-healthy eating pattern like a Mediterranean-style eating pattern,” said Wayne W. Campbell, professor of nutrition science. “This study was not designed to promote red meat intake, and we are not encouraging people who otherwise consume a vegetarian-style eating pattern to begin consuming red meat.”
The study is published online at the American Journal of Clinical Nutrition. It was funded by the Beef Checkoff and the Pork Checkoff, with support from the National Institutes of Health’s Indiana Clinical and Translational Sciences Institute and a National Institutes of Health pre-doctoral training grant through the Ingestive Behavior Research Center at Purdue.
“Most healthy eating pattern recommendations include a broad statement to reduce red meat intake,’” said Lauren E. O’Connor, lead author and recent doctoral degree recipient. “Our study compared Mediterranean-style eating patterns with red meat intake that is typical in the United States, about 3 ounces per day, versus a commonly recommended intake amount that is 3 ounces twice per week. Overall, heart health indicators improved with both Mediterranean-style eating patterns. Interestingly, though, participants’ LDL cholesterol, which is one of the strongest predictors we have to predict the development of cardiovascular disease, improved with typical but not lower red meat intake.”
The study assessed the health-promoting effects of a Mediterranean-style eating pattern, without intended weight loss, for adults who are overweight and at risk for developing heart disease. All 41 study participants – 28 females and 13 males – completed three study phases. The phases included a five-week period of consuming a Mediterranean-style eating pattern containing three ounces per day of lean, unprocessed red meat, an amount of red meat the typical United States resident consumes; a five-week return to their regular eating pattern; and a five-week period of consuming a Mediterranean-style eating pattern with less red meat, three ounces twice weekly, which is commonly recommended for heart health. The order of the typical and lower red meat interventions were randomly assigned among participants.
“It’s also very encouraging that the improvements these people experienced – which included improvements in blood pressure, blood lipids and lipoproteins – were noticeable in five weeks,” Campbell said.
The Mediterranean-style eating pattern, which was ranked No. 1 by Consumer Reports, is recommended by the Dietary Guidelines for Americans. A Mediterranean-style eating pattern has clinically proven effects on health especially related to heart health and risks for heart disease such as heart attack or stroke.
“The composition of a Mediterranean-style eating pattern varies across countries and cultures,” Campbell said. “What is common across most Mediterranean regions is consumption of olive oil, fruit, vegetables and legumes, but protein sources depend on what country and geographic region. If they live on the coast, they will eat more seafood, but if they live inland they will eat more red meat.”
The American Journal of Clinical Nutrition is published by the American Society for Nutrition.
Writer: Amy Patterson Neubert, 765-494-9723, apatterson@purdue.edu
Sources: Wayne Campbell, campbeww@purdue.edu
Lauren O’Connor, leoconno@purdue.edu
Note to Journalists: Journalists interested in a copy of the American Journal of Clinical Nutrition article can contact Amy Patterson Neubert, Purdue News Service, 765-494-9723, apatterson@purdue.edu
ABSTRACT
Background: A Mediterranean-Style Eating Pattern (Mediterranean Pattern) is often described as low in red meat. Research shows that lean unprocessed red meat can be incorporated into healthy eating patterns to improve cardiometabolic disease risk factors (CMD-RF).
Objective: We assessed the effects of consuming different amounts of lean unprocessed red meat in a Mediterranean Pattern on CMD-RF. We hypothesized that consuming a Mediterranean Pattern would improve CMD-RF and red meat intake would not influence these improvements.
Methods: In an investigator-blinded, randomized, crossover, controlled feeding trial, 41 subjects (aged 46 ± 2 y, BMI 30.5 ± 0.6kg/m2) were provided a Mediterranean Pattern for two 5-wk interventions separated by 4-wk of self-selected eating. The Mediterranean Patterns contained ~500g [typical U.S. intake (Med-Red)] and ~200 g [commonly recommended intake in heart healthy eating patterns (Med-Control)] of lean unprocessed beef/pork/wk. Red meat intake was compensated by poultry and other protein-rich foods. Baseline and post-intervention outcomes included fasting blood pressure, serum lipids, lipoproteins, glucose, insulin, and ambulatory blood pressure. Presented data are adjusted for age, sex and body mass at each time point. (p<0.05).
Results: Total cholesterol decreased but greater reductions occurred with Med-Red compared to Med-Control [- 0.4 ± 0.1 and – 0.2 ± 0.1 mmol/L, respectively, intervention*time=0.045]. LDL decreased with Med-Red but was unchanged with Med-Control [-0.3 ± 0.1 and – 0.1 ± 0.1 mmol/L, respectively, intervention*time=0.038] while HDL concentrations decreased non-differentially [-0.1 ± 0.0 mmol/L]. Triglycerides, total cholesterol; HDL, glucose, and insulin did not change with either Med-Red or Med-Control. All blood pressure parameters improved, except during sleep, independent of red meat intake amount.
Conclusion: Adults who are overweight or moderately obese may improve multiple cardiometabolic disease risk factors by adopting a Mediterranean-style eating pattern without or with reductions in red meat intake when red meats are lean and unprocessed.