Instead, the review emphasizes mechanistic and observational evidence to explain how optimal selenium intake and selenium status may be important. At the same time, the authors point out that both selenium deficiency and selenium excess can be detrimental. There seems to be a U-shaped relationship between selenium status and good health and longevity [Pierce & Mackrill 2026].
Chen et al say that “oxidative stress, redox signaling, endothelial activation, and inflammation contribute to atherosclerosis and myocardial injury”. So, there is a mechanistic rationale for selenium to have a cardioprotective effect. “Selenium-dependent enzymes provide a plausible connection because glutathione peroxidases and thioredoxin reductases participate in peroxide reduction and redox regulation” [Chen 2026].
Generally, observational studies show low selenium status associated with increased risk of cardiovascular diseases. However, interventional studies have not shown clearly that selenium supplementation reduces the risk of cardiovascular diseases [Chen 2026].
Chen et al analyzed the relevant research for the period 2005-2026. They concluded that there is not enough evidence to support a program of universal selenium supplement for protection against cardiovascular disease [Chen 2026].
