Selenium Delays Cognitive Decline

In the Swedish KiSel-10 clinical trial, the study participants had an average age of 78 years at the start of the study [Alehagen 2013]. Their serum selenium concentration at baseline was at a deficiency level (mean: 67.1 mcg/L).

Woman meditating
Diet, exercise, and meditation are all important to good brain health. Dietary and supplemental selenium crosses the blood-brain barrier. Supply of selenium to the brain has a higher priority than supply to other organs. Low selenium status is associated with cognitive decline.

Moreover, the low selenium status of the elderly Swedish citizens was significantly associated with relatively high mortality risk [Alehagen 2016]. Daily supplementation with 200 mcg of a selenium-enriched yeast preparation together with 200 mg of Coenzyme Q10 raised the study participants’ serum selenium levels to 210 mcg/L and reduced the risk of cardiovascular mortality [Alehagen 2022a].

The four years of joint supplementation were associated with the following positive health outcomes: read more

Selenium Supplementation and Alzheimer’s Disease

Clinical studies show a clear correlation between Alzheimer’s Disease and low selenium status.  Lower selenium status is associated with worse cognitive decline [Aaseth 2016].

In many regions of Europe and the Middle East, there is poor selenium content in the soil and, accordingly, lower intake of selenium from food sources [Stoffaneller & Morse 2015; Winther 2020].

Woman with Alzheimer's
Adequate levels of selenium are essential for brain function; in fact, the brain is one of the organs that is supplied with selenium at the expense of other organs and tissues in times of low selenium intake. Selenoprotein P plays a special role in delivering selenium to the brain and the neurons. Some of the glutathione peroxidase and thioredoxin reductase selenoenzymes are important intracellular antioxidants in neurons and glia cells of the central nervous system.

The daily intake of selenium from food in many European countries is well below the amount needed for optimal function of important selenoproteins. The needed intake of selenium from food is  estimated to be at least 105 mcg per day [Winther 2020, fig. 2].

Using evidence from human studies in various countries, Prof. Jan Aaseth and colleagues have documented the association between lower selenium  status and Alzheimer’s Disease and/or cognitive impairment [Aaseth 2016]. read more