Effects of plant protein and animal protein on lipid profile, body weight and body mass index on patients with hypercholesterolemia: a systematic review and meta-analysis

Abstract

We conducted a meta-analysis on the effect of plant protein or animal protein on body weight (BW), body mass index (BMI) and blood lipid profiles in patients with hypercholesterolemia. We used subject and free words to search PubMed, Embase and Cochrane Library databases. The risk-of-bias evaluation tool was used to assess literature quality. Data merging and statistical analyses were carried out using Review Manager 5.3 and Stata 13.0. All indicators were expressed as the mean difference (MD) and 95% confidence interval (95% CI). The heterogeneity test was conducted according to I2 and Q tests. We used Egger's test to evaluate publication bias quantitatively. This was a meta-analysis of intervention trials. Thirty-two studies (1562 patients) were included. The quality of the included studies was acceptable. Compared with consumption of animal protein, plant protein reduced total cholesterol (TC) (MD = - 0.19mmol/L, 95% CI - 0.26, - 0.12), triglyceride (MD = - 0.07mmol/L, 95% CI - 0.13, - 0.02), low-density lipoprotein cholesterol (LDL-C) (MD = - 0.19mmol/L, 95% CI - 0.26, - 0.13), very low-density lipoprotein cholesterol (MD = - 0.05mmol/L, 95% CI - 0.09, - 0.01), TC/LDL-C ratio (MD = - 0.17, 95% CI - 0.32, - 0.02) and LDL-C/HDL-C ratio (MD = - 0.20, 95% CI - 0.33, - 0.06) significantly and increased high-density lipoprotein cholesterol (HDL-C) (MD = 0.03mmol/L, 95% CI 0.01, 0.06) levels, but had no effect on BW (MD = - 0.41kg, 95% CI - 2.14, 1.33) or BMI (MD = 0.11kg/m2, 95% CI - 0.51, 0.73). Compared with animal protein, consumption of plant protein could improve lipid profile in patients with hypercholesterolemia.