Data from randomized controlled trials were gathered and analyzed to determine the effect of different red meat consumption amounts on cardiovascular risk factors. Whether the consumption amounts were ≥0.5 servings/day or <0.5 servings/day, values of blood lipids, lipoproteins, and/or blood pressures were not significantly affected.
Cardiovascular disease (CVD) ranks as one of the leading causes of death in North America. Red meat consumption has been associated with a higher incidence of CVD, but this notion continues to be challenged due to inconsistent evidence throughout literature. In a study published in the American Journal of Clinical Nutrition, researchers conducted a meta-analysis using literature studies to determine a relationship between red meat consumption amounts and changes in CVD risk factors after several weeks.
After data analysis, the results show no significant difference in values for risk factors, such as blood lipids, lipoproteins, and/or blood pressures, between the two groups after meat consumption. These results are generalizable as it includes a variety of populations, dietary patterns and types of red meat. Although median daily total red meat intake in the intervention group was high at 2 servings/day relative to the average American red meat consumption of 1.2 servings/day, the range was large (1.0-7.1 servings/day). Red meat consumption amounts were further categorized into smaller ranges: 1.0-1.9, 2.0-2.9 and >3.0 servings/day. After the analysis was re-conducted using these categories, all the consumption amounts, except for the >3.0 servings/day group, resulted in risk factor values that did not differ from the comparator group once again. On the other hand, those who consumed >3.0 servings of red meat/day showed increased levels of high-density lipoproteins, the ‘good cholesterol’, compared to those who consumed lower amounts of red meats.
Overall, these findings contradict previous epidemiologic studies, which support that consumption of red meat is associated with higher incidences of CVD-related mortality and morbidity. However, these studies differ from randomized control trial such that they are conducted over the course of years, and are not suitable to determine cause-effect relationships. Thus, future efforts and research are needed to improve scientific understanding and communication to the public about the effects of red meat on human health according to different research designs.
Written By: Kim Gotera, BMSc