Studies have long suggested that the mineral selenium may have powerful brain benefits.

For example, age-related decreases in selenium levels correlate with an increased risk of cognitive decline.^1-6

Now, a promising animal study confirms that selenium can reduce age-related cognitive decline by increasing the formation of new brain cells. And it does so in the area of the brain important for learning and memory formation.⁷

Neurogenesis and Cognitive Decline

The hippocampus is a brain region that is critical for learning and the formation of new memories.^8-10

Unlike most regions of the brain, some of the cells here retain the ability to divide and grow throughout life. This formation of new brain cells is called neurogenesis.¹¹

Adult neurogenesis is considered to be one of the main reasons brains have the ability to adapt, learn, and form new memories even in later life.^10,12

Unfortunately, neurogenesis tends to decline with advancing age. This inability to refresh the cells of the hippocampus may be an important contributor to age-related cognitive decline.⁷

Boosting neurogenesis, on the other hand, could provide a way to reduce or even prevent cognitive decline.^12,13 That's where selenium comes in.

Selenium’s Protective Effects

Animal studies have shown that selenium may play a role in protecting against normal brain aging.¹⁴ The transporter protein for selenium has been shown to protect the brain against selenium deficiency, promote neurogenesis and prevent cognitive decline.¹⁵

In human studies, low selenium levels have been associated with a rapid decline in cognitive function.⁵

In a study of 320 heart failure patients, subjects with higher selenoprotein levels (a marker of plasma selenium status) performed better in global cognitive test scales as compared to those with lower levels.¹⁶

There is preclinical evidence that selenium deficiency induces inflammation in the brain,¹⁷ and is associated with age-related disorders such as Alzheimer's disease.^15,18,19

Studies have highlighted the potential role of selenium in neurodegenerative diseases. A meta-analysis compared brain tissue selenium levels' status of Alzheimer's patients with those without Alzheimer's. This study found that the Alzheimer's patients had significantly lower selenium status in their brains as compared to those without Alzehimer's.²

Another meta-analysis indicated that Alzheimer's patients are strongly associated with lower selenium concentrations compared to healthy people.²⁰

In animal models of Alzheimer's disease, selenium intake also reduces the accumulation of abnormal proteins associated with the disease, including hyperphosphorylated tau and beta-amyloid.^15,18,19

Boosting Neurogenesis in Older Adults

A preclinical study showed that exercise can trigger the growth of new brain cells in the hippocampus and enhance cognitive function.⁷

In a mouse study published in 2022, researchers demonstrated that with exercise comes a significant increase in blood levels of SEPP1, the main protein that supplies selenium to the brain. Exercise led to more than a doubling of SEPP1 levels.⁷

To test whether increased selenium brain levels directly led to neurogenesis, scientists applied selenium to brain cells in cell culture. The mineral stimulated their proliferation and signs of neurogenesis.

Supplying selenium to mice had the same effect, resulting in more than a three-fold increase in the number of dividing cells in the hippocampus.

Most impressively, when elderly mice were given selenium in their drinking water, increased neurogenesis was accompanied by significant improvements in tests of learning and memory.

Summary

The mineral selenium has been shown to be a crucial component in maintaining brain health into older age.

A recent animal study found that delivery of selenium to the brain promotes neurogenesis, the ability of the brain to grow new cells. In the hippocampus, these cells support cognitive function and support memory and learning. This could be a crucial area in the search for defenders against age-related decline.

Lower selenium levels have also been tied to cognitive decline and Alzheimer's disease in humans.

Oral intake of selenium is an effective way to increase delivery of the nutrient to the brain and support healthy cognitive function.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.

References

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