Healthy diet could improve semen parameters in male factor infertility: a systematic review of observational studies

Consuming a healthy diet along with nutrients could improve the quality and fecundability reports the results of a systematic review published in March 2017 in Journal of Human Reproduction Update.

Recent available data estimate that around 50 million couple worldwide experience infertility and were unable to conceive after 5 years of marriage. In US, CDC stats that about 11% of U.S. couples have impaired fertility.

Male factor infertility accounts for 25% to 30% of cases and the number is increasing globally because of worldwide decline in semen quality.

Many environmental and lifestyle factors have been blamed for the decline in sperm count. One of the important possible determinant of sperm quality is diet and nutrients with only few small random RCTs available in literature.

The researchers conducted a detailed systematic review of available literature from till November 2016 following the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

All cross sectional, prospective and retrospective case -control studies in which men were responsible for fertility problems with well-defined semen parameters were included in the analysis.

Out of 1944 articles delineated, 35 were selected for quantitative analysis.

It was seen that:

Diets that are high  in saturated and trans-fat and low in omega-3 fatty acids, some antioxidants (vitamin E, vitamin C, β-carotene, selenium, zinc, cryptoxanthin and lycopene), other vitamins (vitamin D and folate) were all associated with several  low semen parameters.

Consumption of seafood, fish, low fat dairy, cereals, vegetables and fruits were positively associated with several sperm quality parameters.

Processed food, potatoes, soy, full fat dairy, coffee, alcohol, sweetened beverages and desserts are all responsible for falling semen parameters.

Men who consumed too much alcohol, caffeine, processed meat and red meat decreased the chances of pregnancy in their partners.

The authors concluded that making healthy diet a part of your lifestyle could improve the couple chances of fertilization by improving the semen parameters. But, observational nature of the study results only prove association and not causation.

Large Randomized Prospective studies in future should be designed to confirm the causation.