Does fish oil supplementation affect testicular function in young men?

This study investigated if fish oil supplementation improves semen quality and reproductive hormone (RH) levels in young men. 

They found that fish oil supplementation was associated with better semen quality and RH levels. 

Male infertility (MI) is affects around 50% of infertile couples. In recent years sperm quality has been declining. The cause of the decline in sperm quality is unclear. Many factors may influence sperm quality. Exposure to some chemicals can damage sperm. Preventing sperm damage is important. 

Diet could play an important role in improving sperm quality. A number of dietary factors have been identified. Fish oils are one of these. They contain a number of nutrients that may improve sperm quality. Fish oil supplementation can be used to improve fish oil intake. There is conflicting evidence on whether fish oil supplementation improves sperm quality in men with MI. 

This study included 1679 young men. Participants provided a semen sample for assessing sperm quality. A blood sample was also taken to measure RH levels. Testosterone (T) is a male RH. Other RHs included follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The testis were examined by a physician. Participants completed a questionnaire on diet and lifestyle. 

5.8% of men reported using fish oil supplements. Men that reported fish oil supplementation had larger testes and higher sperm count compared to those without fish oil supplementation. Also, men reporting fish oil supplementation of more than 60 days had larges testes and higher semen volume than those with a lower than 60 days supplementation.

Men taking fish oil supplements had lower FSH and LH levels and higher T levels. Lower FSH and higher T to LH ratio are associated with better fertility. Compared to other multivitamins, men taking fish oil supplements had the highest semen volume and concentration. 

The authors concluded that fish oil supplementation was associated with better sperm quality and RH levels.

This study only included healthy young men. Whether fish oil supplementation improves semen in men with infertility is still unknown. There was no data on the dose or type of fish oil supplements. More controlled studies are needed. 

If you have any concerns regarding infertility please consult with your physician.