We aimed to evaluate the combined effects of a vegetarian diet (VD) and exercise on total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), systolic blood pressure (SBP), and diastolic blood pressure (DBP) parameters. A literature search was conducted in electronic databases from build to February 27, 2022. Data were synthesized using random effects model and were expressed as standardized mean difference (SMD)/weighted mean difference (WMD) and 95% confidence interval (CI). Overall, 27 trials with 9,251 participants were included. Pooled results indicated that the combination of a VD and exercise significantly reduced TC (SMD: -0.524; 95% CI: -0.602, -0.446; p < 0.001), LDL-C (SMD: -0.379; 95% CI: -0.471, -0.287; p < 0.001), HDL-C (SMD: -0.213; 95% CI: -0.299, -0.126; p < 0.001), TG (SMD: -0.090; 95% CI: -0.160, -0.020; p = 0.012), SBP (WMD: -7.664 mm Hg; 95% CI: -9.219, -6.109 mm Hg; p < 0.001), and DBP (WMD: -4.347 mm Hg; 95% CI: -5.099, -3.596 mm Hg; p < 0.001). These parameters were reduced more following a low-fat VD, or a mixed high-frequency exercise, especially under strict supervision. Surprisingly, the decreased HDL-C due to VD was observed to recover with the prolongation of exercise.
Keywords: Blood lipids; blood pressure; meta-analysis; physical activity; vegetarian diet.