People with or at a high risk of cardiovascular disease who maintain a vegetarian diet for 6 months or longer show significant improvements in key risk factors, including cholesterol, glycemic control and body weight, a meta-analysis of randomized controlled trials shows.
The study was published online July 25 in JAMA Network Open.
“The greatest improvements in hemoglobin A1c and low-density lipoprotein cholesterol (LDL-C) were observed in individuals with type 2 diabetes and people at high risk of cardiovascular disease, highlighting the potential protective and synergistic effects of vegetarian diets for the primary prevention of cardiovascular disease,”.
Poor diet is well-established as increasing the morbidity and mortality associated with cardiovascular disease; however, although data has linked vegetarian diets to cardiovascular disease prevention in the general population, research on the effectiveness of such diets in people at high risk of cardiovascular disease is lacking.
Greater Decreases in LDL-C, A1c, and Body Weight With Vegetarian Diets
Researchers identified 20 randomized controlled trials involving vegetarian diets that included 1878 adults with or at a high risk of cardiovascular disease and included measurements of LDL-C, A1c, or systolic blood pressure.
The studies were conducted in the United States, Asia, Europe, and New Zealand between 1990 and 2021. Sample sizes ranged from 12 to 291 participants.
The mean range age of participants was 28 to 64 years. Studies included patients with cardiovascular disease (four studies), diabetes (seven studies), and those with at least two cardiovascular risk factors (nine studies).
The most commonly prescribed diets were vegan (plant-based foods only), lacto-ovo-vegetarian (excluded meat, poultry and seafood but allowing dairy products and eggs), and lacto-vegetarian (excluding meat, poultry, seafood and eggs but allowing dairy products such as cheese).
Overall, those who consumed a vegetarian diet for an average of 6 months, versus comparison diets, had significantly greater decreases in LDL-C (6.6 mg/dL beyond the reduction achieved with standard therapy); A1c (0.24%); and body weight (3.4 kg).
