Eating red meat is bad for our health, and many scientific studies show how it negatively impacts our well-being. A new study conducted at Harvard T.H. Chan School of Public Health and Purdue University indicate that diets replacing red meat with plant proteins lead to a reduction in risk factors for CVD. The results of the survey were published in the Circulation journal (April 2019).
CROSS COMPARISON BETWEEN MULTIPLE DIETS
In order to reach these results, a systematic review was performed of the studies published before July 2017 in PubMed (the US National Library of Medicine of the National Institute of Health, which include over 30 million citations of biomedical literature such as biology journals, online books, and MEDLINE-database of life sciences and biomedical disciplines). This is the first updated meta-analysis of Randomized Control Trials evaluating the effects of red meat on CVD risk factors, comparing it to control diets in which red meat was replaced with a variety of foods. The researchers compared the classic red meat-rich diets with different types of diets: high-quality vegetable protein sources (legumes, soy, and nuts); chicken, poultry and fish; fish only; poultry only; mixed sources of animal protein (including dairy); carbohydrates (low-quality refined grains and simple sugars such as white bread, pasta, rice, crackers, and biscuits).
In total, 36 randomized control trials were included, involving a total of 1,803 participants. Plasma cholesterol, triglyceride, lipoproteins, and blood pressure (all CVD risk factors) levels of participants consuming a red meat diet were compared to that of all other types of diets. By this comparison, the researchers found that there weren’t significant difference in the concentrations of lipoproteins, total cholesterol, or blood pressure. Although, diets high in red meat resulted in higher triglyceride levels than all other diets. The key takeaway is that diets with higher amounts of high-quality plant proteins (like legumes, soy, and nuts), on the other hand, led to lower cholesterol levels than diets rich in red meat.
REPLACE RED MEAT WITH LEGUMES AND NUTS
According to previous studies, replacing red meat with high-quality vegetable protein sources, rather than low-quality poultry, fish, or carbohydrate, leads to more favorable changes in blood lipid and lipoprotein concentrations. Furthermore, the results are consistent with long-term epidemiological studies that observe a lower incidences of heart attack risk when red meat is replaced with nuts and other plant proteins. The heterogeneity found in previous studies regarding the effects of red meat on CVD risk factors may be attributed to the composition of the control diet. For this reason, professionals state that future studies should take into account more specific comparisons.
To conclude, experts recommend to avoid red meats as much as possible and instead to consume vegetarian diets with high quality plant proteins (legumes and nuts), both for personal health benefits and for food sustainability purposes.
Marta Guasch-Ferré et al. – “Meta-Analysis of Randomized Controlled Trials of Red Meat Consumption in Comparison with Various Comparison Diets on Cardiovascular Risk Factors” – Circulation (April 2019)