Can Selenium Supplementation Increase Testosterone in Men?

As men grow older, maintaining healthy testosterone levels becomes increasingly challenging. Certain minerals like zinc and vitamin D are already well established as supporting healthy testosterone production. But emerging research suggests the trace mineral selenium may also influence testosterone concentrations in men. This article reviews the current scientific literature surrounding selenium and testosterone.

Selenium and Male Health

Selenium is an essential dietary mineral with antioxidant properties found abundantly in foods like brazil nuts, eggs, liver and yellowfin tuna. Selenium acts as a vital structural component of enzymes throughout the human body tied to optimal metabolic function. Deficiency negatively impacts thyroid metabolism, infertility and immune activity.

Population data reveals parts of Europe, Russia and China suffer from endemic low dietary selenium intake which tracks closely with reproductive issues. This correlation helped spawn interest around selenium and testosterone.

But before analyzing key studies, it’s important to understand selenium’s theoretical mechanisms of action regarding testosterone. 

How Might Selenium Affect Testosterone? 

Researchers have identified two central pathways by which selenium supplements may support healthy testosterone balance:

1. Optimizing Thyroid Function

Subclinical hypothyroidism from selenium deficiency impairs healthy pituitary gland signaling to the testes, depressing testosterone synthesis. Selenium supplementation may reverse this suppression by preventing hypothyroidism. 

2. Direct Steroidogenesis Activation

Animal research indicates selenium nanoparticles may further stimulate testosterone production directly by enhancing expression of steroidogenesis enzymes like CYP11A1 inside Leydig cells.

So in theory, selenium may benefit testosterone via thyroid-mediated and direct pathways. But what effects show up consistently across clinical research?

Analyzing the Clinical Trial Evidence

Surprisingly few trials have examined selenium and testosterone in humans. However, two 2020 studies expanded current evidence: 

In the first double-blind trial, researchers gave men with subnormal testosterone levels 200mcg daily selenium yeast or placebo over 12 weeks. Total testosterone increased 15.8% in the selenium group compared to only 6.2% in placebo. Libido also improved significantly more in selenium recipients. 

This small pilot study supports selenium benefits among middle aged men with lagging testosterone levels, matching epidemiological links between deficiency and hypogonadism prevalence. (1)

Another trial added selenium yeast or placebo to testosterone therapy taken by older men over 12 months. 200mcg selenium administration enhanced free testosterone levels from the exogenous testosterone cream by an additional 15% after both 6 and 12 months compared to medication only.

By optimizing free testosterone bioavailability, selenium appeared to maximize topical testosterone treatment efficacy in androgen deficient subjects. (2)

While research remains limited, these latest quality investigations provide growing evidentiary momentum that selenium supplementation likely supports healthy testosterone metabolism in men – especially those with identified hypogonadism or suboptimal levels. 

However, more extensive clinical data is still needed to confirm effects across wider populations, ages and baseline health statuses before drawing firmer conclusions.

Conclusion & Next Steps 

If you are a man over 40 struggling with possible low testosterone symptoms, ask your doctor to check both total and free testosterone blood levels along with selenium status. Many labs now offer comprehensive male hormone panels including selenium and total antioxidant function.

Correcting any identified selenium deficiencies through dietary enrichment or supplements provides relatively inexpensive and benign but possibly impactful intervention for sustaining healthy testosterone production with advancing paternal age.