Effect of vitamin D supplementation on blood lipids in patients with metabolic syndrome: a meta-analysis

Background Vitamin D, a fat-soluble vitamin critical for bone metabolism, has recently been implicated in metabolic homeostasis. Growing evidence suggests its potential role in modulating lipid profiles in metabolic syndrome. Objectives This meta-analysis evaluated the effects of vitamin D supplementation on blood lipids in patients with metabolic syndrome. Methods We searched the randomized controlled trials from 1948 to February 1, 2026 involving vitamin D supplementation treatment for patients with metabolic syndrome from PubMed, EMBASE, Cochrane library, SinoMed, and conducted a meta-analysis. The meta-analysis was registered on the PROSPERO, the registration number is CRD42024591657. Results Finally, seven trials were included in the meta-analysis. The results demonstrated that vitamin D supplementation significantly reduced triglyceride levels (MD = −12.64, 95% CI −21.23∼−4.04, P = 0.004). However, no significant differences were observed in total cholesterol or low-density lipoprotein cholesterol levels between the vitamin D treated groups and control groups. Notably, vitamin D supplementation showed potential benefits in increasing high-density lipoprotein cholesterol levels particularly with daily regimens (MD = 1.77, 95% CI 0.90∼2.64 P < 0.0001, I 2 = 35%). Conclusions Our meta-analysis confirmed the effects of vitamin D in the management of triglyceride level in metabolic syndrome patients. Vitamin D supplementation showed potential benefits on increasing the high-density lipoprotein cholesterol levels especially with daily regimens. More randomized controlled trials are needed to confirm the result.