Men who follow a Mediterranean-style diet have higher sperm counts than men who eat unhealthily, according to a small new research study.
The Mediterranean-style Dietary Approaches to Stop Hypertension (DASH) diet is rich in fruit, vegetables and low-fat dairy products, and low in processed meat, salt and sugary drinks. It is recommended by the American Heart Association to help prevent high blood pressure, but its effect on male fertility had not previously been studied.
The team led by Dr Ana Cutillas-Tolín of the University of Murcia School of Medicine in Spain recruited 209 healthy male university students who completed a questionnaire where they reported how often they had eaten various food items over a year. They also gave semen and blood samples.
The researchers scored how closely the men stuck to a DASH diet and tested the blood samples for hormone levels and the sperm samples sperm count, proportion of moving sperm and sperm shape.
The men who ate a diet rich in fruit and vegetables had sperm counts 65 percent higher than those whose diets were high in processed meat, salt and sugary drinks. They also had 74 percent more moving sperm and 31 percent more sperm of a normal size and shape.
The researchers did not find a link between diet and levels of male reproductive hormones like testosterone.
Although the research found that men with healthy diets had higher sperm counts, the study does not prove a difference in functional fertility. The participants were healthy young men who had not been diagnosed with fertility problems. It is not known if the same patterns would be found in infertile men or other male populations. The researchers say that more research is needed in this area.
Another limitation is that the research relied on participants accurately recalling their diet.
Dr Muhammad Imran Omar, a researcher at the University of Aberdeen who was not involved in the study, told Reuters: 'The findings of this study cannot be generalised due to various limitations such as small sample size, and healthy volunteers, and the study should be extended to other populations. However there is enough scientific evidence to suggest that fruits, vegetables and low-fat dairy foods are important for a healthy lifestyle and reproductive health.'
The research was published in the journal Human Reproduction.