Selenium supplementation can improve male fertility

Infertility due to poor sperm quality in men is an increasing problem. Although there may be several causes, it appears that widespread selenium deficiency is a significant factor. A lack of selenium can lead to hormonal imbalances, changes in the structure of sperm cells, and make them more vulnerable to damage caused by oxidative stress.

On the other hand, selenium supplementation may help improve several parameters of sperm quality and thereby increase the chance of pregnancy, according to a review article published in the Journal of Trace Elements in Medicine and Biology. The authors emphasize that organic forms of selenium, such as selenium yeast, should be chosen, as they have higher bioavailability.
Selenium is a trace element that is part of around 25-30 different selenoproteins with importance for energy production, metabolism, the immune system, the body’s antioxidant defense, and overall health. It is well known that selenium plays a role in fertility in both sexes. The new review article therefore aimed to include new perspectives regarding the importance of different selenium compounds for male fertility and sperm function across multiple parameters. The authors also examined selenium’s interactions with other nutrients and the therapeutic differences between different types of selenium supplements.
Trawling databases such as PubMed, Scopus, and Web of Science, the researchers identified a range of studies published between 2000 and 2025. The review revealed that supplementation with organic selenium had a much better effect on blood levels of selenoprotein P, which serves as a marker of the body’s selenium status, and GPXs, which function as powerful antioxidants.
Human studies have shown that supplementation with 100 micrograms of selenium daily can improve hormonal balance as well as sperm viability and motility, thereby resulting in an 11 percent greater chance of becoming a father. On the other hand, excessive selenium intake (over 300 micrograms daily) may impair sperm motility. Additional supplementation with vitamin E and zinc may further improve the antioxidant defense of sperm cells.

Selenium’s many functions in male fertility

In the introduction to the review article, the authors further describe the functions of the different selenoproteins in male fertility. As mentioned, selenoprotein P circulates in the blood and is then taken up by the body’s cells, which produce other selenoproteins as needed.
Overall, selenoproteins are important for the following aspects of male fertility:

• Testosterone production
• Spermatogenesis, which is the formation of mature sperm cells from stem cells in the testes
• Sperm motility, which is crucial for sperm to swim the long distance to the woman’s egg in the fallopian tube
• Morphology, which includes the normal shape of sperm cells
• Integrity of sperm DNA, which is crucial to ensure that a fertilized egg is not rejected
• Antioxidant protection, which protects the reproductive organs and sperm cells from damage caused by oxidative stress

The authors further describe how the male reproductive organs, including the testes, epididymis, and sperm cells, are highly sensitive to oxidative stress. This is a condition in which there are too many potentially harmful free radicals relative to protective antioxidants. We all generate free radicals during various metabolic processes, and this production is greatly increased by tobacco smoke, toxins, lack of sleep, obesity, elevated insulin levels, and stress.
The reason why sperm cells are so sensitive to free radicals is that their membranes contain large amounts of polyunsaturated fatty acids. When these are attacked, it causes chain reactions within the sperm cells and between cells. In addition, sperm cells have a poor ability to repair damage to their DNA. This can lead to something called DNA fragmentation. This means that even if a sperm cell successfully fertilizes the woman’s egg, the egg cannot develop properly and is therefore rejected.
Here, the selenoproteins GPX1 and GPX4, as well as selenoprotein P, have a special ability to neutralize certain free radicals known as hydrogen peroxides. In this way, these selenoproteins can protect the reproductive organs and sperm cells from damage caused by oxidative stress. This also includes protection of sperm chromatin, which consists of DNA and proteins, as well as the sperm cell’s mitochondria, which are responsible for the important energy metabolism that enables sperm cells to swim more efficiently toward the egg.

Sources of selenium, causes of deficiency, and relevant supplementation

Selenium is found in meat, organ meats such as liver and heart, as well as fish, shellfish, eggs, and Brazil nuts. The content in grains and other crops depends on soil conditions. Since soils in Europe are generally low in selenium, this contributes to the widespread deficiency.
According to the Nordic Nutrition Recommendations, women and men should consume 75 and 90 micrograms of selenium daily, respectively. As stated in the review article, a selenium supplement of 100 micrograms may increase male fertility. Supplements should be based on selenium yeast or other organic compounds. As noted, vitamin E and zinc from diet or supplements may enhance the effect. In supplements aimed at male fertility, selenium has also been combined with Q10 to improve sperm energy metabolism and the body’s overall antioxidant defense.

• Farmers have known for decades that selenium deficiency reduces fertility in animals, and that selenium supplementation is necessary.

References:

Neeraj Patel et al. Selenium supplementation and male fertility: Mechanistic insights and therapeutic potential. Journal of Trace Elements in Medicine and Biology. 2026

Rasmus Dalsgaard. Græsning kan give mangel på selen. Maskinbladet 2020