Stroke Archives - Seleniumfacts.com

A Chinese study has shown that there is a significant negative association between plasma selenium concentrations and the risk of a first stroke in males but not in females. This is not the first time that sex differences have been reported relative to selenium metabolism. More on that later.

Picture of the brain — Typically, there were many more cases of first ischemic stroke, usually caused by a blood clot, than there are cases of first hemorrhagic stroke, usually caused when a blood vessel leaks or breaks open). Adequate selenium supply to the brain may protect against the risk of stroke.

Plasma Selenium Levels and the Risk of a First Stroke

The Chinese researchers analyzed the results from a nested case-control study with 1255 first stroke cases and 1255 matched controls [Hu 2021].

They found that males (but not females) with plasma selenium concentrations above 94 micrograms per liter had significantly less risk of a first stroke of any kind and significantly less risk of a first ischemic stroke.
There was also a stronger negative association between plasma selenium levels and first strokes of all kinds — ischemic, hemorrhagic, or unidentified — in males with higher vitamin E levels.
There was no significant association between plasma selenium levels and first hemorrhagic stroke risk in either males or females.

N.B. In this study, there were many more cases of first ischemic stroke (n=1079) than there are cases of first hemorrhagic stroke (n=171). Five cases were of uncertain origin.

Evidence from Other Studies of Selenium Level and Stroke Risk

The results from studies of selenium level and stroke risk have been somewhat confusing to date: read more

Milestones in early selenium research

1817 Swedish chemist Jöns Jakob Berzelius discovers selenium

1957 Biochemist Klaus Schwarz shows that selenium in microscopic amounts has a vital importance for mammalian health

1969 Professor J.T. Rotruck discovers that selenium has a biochemical role as a component of the antioxidant enzyme glutathione peroxidase

1969 Professors R.J. Shamberger and D.V. Frost report a possible protective effect of selenium against cancer in humans

1973 Professor J.T. Rotruck identifies the enzyme glutathione peroxidase as a selenium-dependent protein

1977 Professor G.N. Schrauzer publishes cancer mortality correlation studies showing an inverse correlation between dietary intakes of selenium and cancer mortality in 27 countries

1988 Professor G.Q Yang summarizes the lessons learned about the selenium-related endemic diseases Keshan disease and Kashin-Beck disease and about the importance of adequate daily selenium intakes

1989 Professor G.G. Duthie publishes evidence for a role of selenium in the prevention of cardiovascular disease

1993 Researcher W.J. Blot publishes the results of the Nutrition Intervention Trials in Linxian, China, showing that supplementation with a combination of selenium and other antioxidants reduces the risk of cancer

1994 Professor G.N. Schrauzer publishes evidence that selenium is important in the maintenance and therapy of HIV-infected patients

1996 Professor Larry Clark publishes the results of a randomized controlled trial – the Nutritional Prevention of Cancer study -- that shows selenium's cancer-protective effects on colon cancer, lung cancer, and prostate cancer

1997 Professor G.F. Combs summarizes the evidence for the protective effects of selenium against cancer

1999 Professor J.E. Oldfield publishes his Selenium World Atlas, mapping areas of selenium deficiency around the world

2000 Researcher O.A. Levander publishes evidence showing an anti-viral effect of selenium

2002 Researcher R. Gärtner shows that supplementation with selenium reduces inflammation in patients with autoimmune thyroiditis

2002 Researcher Margaret Rayman presents the arguments for increasing selenium intakes to realize selenium’s antioxidant and anti-viral and anti-inflammatory effects as well as selenium’s enhancement of immune function and reproductive success.