Cardiovascular health and Vitamin D - review of 127 studies
Vitamin D and cardiovascular health: A systematic review and evidence synthesis from deficiency to toxicity
Brain & Heart. May 2026 doi: 10.36922/BH025250031
Bhaskar Pal1 , Rajdip Goswami2 , Pinki Biswas3®, Debdutta Chakraborty4 , Debasmita Kundu5 , Mainak Chakraborty2®, and Saikat Santra3*
Vitamin D deficiency affects approximately 1.5 billion people worldwide and has been increasingly associated with cardiovascular diseases (CVDs). However, the precise role of vitamin D in cardiovascular health remains unclear due to inconsistent findings across studies. This systematic review critically evaluates the existing literature on the effects of vitamin D status, ranging from deficiency to toxicity, on cardiovascular outcomes. A comprehensive search was conducted in major electronic databases for observational studies and randomized controlled trials examining the relationship between vitamin D levels or supplementation and key outcomes, including hypertension, myocardial infarction, stroke, and vascular calcification. Due to substantial clinical and methodological heterogeneity, findings were synthesized using a structured narrative approach. The evidence indicates a non-linear, U-shaped association between serum vitamin D levels and cardiovascular risk. Vitamin D deficiency has frequently been linked to higher blood pressure and an increased incidence of adverse cardiovascular events in observational studies. Moderate supplementation appears beneficial in deficient individuals, whereas excessive or high-dose supplementation has been associated with detrimental effects, particularly vascular and valvular calcification. Randomized trials have not demonstrated consistent cardiovascular benefits from routine supplementation. Vitamin D may have dose-dependent effects on cardiovascular health, with potential risks at both low and excessive levels. While correcting deficiency may be protective, universal supplementation is not supported for CVD prevention. Well-designed trials are needed to determine optimal dosing, target populations, and long-term cardiovascular safety.