An omega-3 deficiency in oily marine fish may cause some cases of male sterility, according to a US study reported in the Journal of Lipid Research.
Omega-3 fatty acids are long-chain polyunsaturated fatty acids. The most important of them is alpha-linolenic acid (ALA), which our body cannot synthesize itself, so we must provide it with food. Its good sources are mainly linseed and rapeseed oil, soybeans, walnuts, and wheat germ. The other two most important acids in this group are docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), which our body is able to produce from ALA. Especially oily sea fish such as cod, herring, mackerel and salmon are rich in DHA and EPA. Research shows that omega-3 fatty acids have a very beneficial effect on human health – incl. reduce the risk of cardiovascular diseases, some neurological diseases, and even cancer. Their effect on male fertility is less known. Analyzing this aspect of the action of omega-3 acids, scientists from the University of Illinois conducted studies on mice in which the gene encoding the enzyme (delta-6-desaturase) responsible for the synthesis of DHA acid was turned off.
They then analyzed the number, shape and motility of sperm produced by male rodents. In animals deficient in DHA, sperm counts were extremely low. They were also round, not elongated, and had limited mobility, explains Manuel Roquet-Rivera, PhD student who participated in the research. In his opinion, this indicates a disruption of the late stages of spermatogenesis (i.e. the process of sperm formation). As a result, males deficient in DHA were unable to produce offspring.
Their infertility, however, was completely preventable when DHA was added to their diet just after weaned their mother’s milk. It was amazing. When we fed the DHA males to the males, all sperm abnormalities were avoided, explains Roqueta-Rivera.
The authors of the study emphasize that they were able to directly prove for the first time that DHA is very important for male fertility as it regulates the process of sperm formation. Previously, some studies only suggested that men who treat infertility – producing insufficient amounts of sperm or sperm with insufficient mobility – are more likely to be deficient in this fatty acid.
Scientists hope that thanks to their discoveries, DHA can be used in the treatment of male infertility in the future. (PAP)