Diets where red meat is replaced with healthy plant proteins have been shown to reduce risk factors for cardiovascular disease, according to a study from the Harvard TH Chan School of Public Health. This study is the first meta-analysis of randomized controlled trials investigating the health effects of red meat by substituting it for other specific types of food.
Previous results of randomized controlled trials evaluating the effects of red meat on cardiovascular disease risk factors have been lacking. But this study, which draws specific comparisons between diets high in red meat and diets high in other types of foods, shows that replacing red meat with high-quality protein sources results in more favorable changes. cardiovascular risk factors.
Lower total cholesterol and LDL levels
The study included data from 36 randomized controlled trials involving 1,803 people. The researchers compared people who ate red meat to those who ate more of other types of food (chicken, fish, carbohydrates or plant proteins like legumes, soy or nuts), looking at blood levels of cholesterol, triglycerides, lipoproteins and blood pressure, all risk factors for CVD.
The study found that when red meat diets were compared to all other types of diets combined, there were no significant differences in total cholesterol, lipoproteins or blood pressure, although the diets higher in red meat resulted in higher tryglyceride concentrations than the combined diets. However, researchers found that diets high in high-quality plant protein sources like legumes, soy, and nuts resulted in lower levels of total cholesterol and LDL (“bad” cholesterol) compared to diets based on protein. Red meat.
Reduced risk of heart attack
The results are consistent with long-term epidemiological studies that show the risk of heart attack is lower when red meat is substituted with nuts and other plant protein sources, according to the authors.
The results also suggest that the inconsistencies found in previous studies regarding the effects of red meat on cardiovascular risk factors may be due, in part, to the composition of the comparison diet. They recommended that future studies consider specific comparisons.
Meir Stampfer, professor of epidemiology and nutrition and lead author of the study, said: “Asking whether red meat is good or bad is pointless. You have to compare it to something. If you replace burgers with cookies or fries, you won’t be healthier. But if you replace red meat with healthy sources of plant-based protein, like nuts and beans, you get a health benefit. »
The authors recommend adherence to healthy vegetarian and Mediterranean diets, both for their health benefits but also their lower environmental impact.
Marta Guasch-Ferré: Meta-Analysis of Randomized Controlled Trials of Red Meat Consumption in Comparison With Various Comparison Diets on Cardiovascular Risk Factors. Traffic (DOI: 10.1161/CIRCULATIONAHA.118.035225)