Research has shown that vitamin D3 therapy could significantly reduce the risk of a second heart attack in patients who have already experienced one. The study, conducted by Intermountain Health in Salt Lake City, Utah, involved 630 patients with a history of heart attacks. The findings, presented at the 2025 American Heart Association Scientific Sessions, indicated that those who received targeted vitamin D3 treatment had a 50% lower risk of suffering a major cardiac event. This study builds on previous research linking low vitamin D levels to an increased risk of cardiovascular diseases, including hypertension and heart failure.
Participants in the trial were divided into two groups: one received high-dose vitamin D3 treatment, while the other did not. Researchers adjusted dosages to achieve blood levels above 40 ng/mL, with some patients requiring an initial dose of 5,000 IU of vitamin D. Over a period of nearly six years, the study monitored participants’ cardiovascular health, with 107 patients experiencing a major cardiac event. The lead researcher emphasized that no adverse outcomes were reported from administering higher doses of vitamin D3, although she noted the need for further validation of these findings.
Experts like Dr. Bradley Serwer, a cardiologist at VitalSolution, acknowledged the potential of vitamin D3 in reducing heart attack risk. However, he warned that past studies often used insufficient dosages, making it difficult to assess the true effectiveness of supplementation in lower-risk populations. Despite these caveats, the study underscores the significant role of vitamin D in maintaining cardiovascular health and highlights the importance of maintaining optimal blood levels. The results also suggest that vitamin D may act more as a hormone than a vitamin, playing a crucial role in cellular function and organ health, particularly the heart.
While the study offers encouraging insights into the benefits of vitamin D3 for heart attack survivors, researchers caution against overgeneralizing these findings. Further studies are needed to determine the effectiveness of the supplement in lower-risk individuals and to assess long-term benefits and potential risks. The findings, however, mark a significant step forward in understanding the role of vitamin D in cardiovascular health and may lead to new guidelines for its use in heart disease prevention and management.