Eating 75 grams of nuts a day improves vitality, motility and sperm morphology in healthy men aged 21 to 35 years, according to a paper published in Biology of Reproduction.
About 70 million couples have fertility problems in the world, according to the publication, stating that between 30 and 50% of cases are attributable to the male.
Some studies have suggested that human semen quality has declined in industrialized countries, possibly due to pollution, poor lifestyle habits and a Western-style diet.
Dr. Wendie Robbins of the University of California at Los Angeles and his team investigated whether increased polyunsaturated fatty acids (AGP), which are essential for sperm maturation may increase sperm quality in men who eat a diet Western style.
According to experts, the best sources to find these fatty acids in this diet are fish and fish oil supplements, flax seeds and walnuts, which are especially rich in linolenic acid (omega 3).
The study, which received support from the California Walnut Commission, has shown benefits in the strength of the sperm of those who consumed nuts, although experts caution that more research is needed to examine whether the benefits can be extrapolated to fertility.
The researchers selected 117 healthy men aged between 21 and 35 who consumed a Western-style diet and divided into two groups: one with 58 members who avoided the consumption of nuts and another with 59, ate 75 grams of nuts a day.
Previous studies have indicated that 75 grams of nuts could be the dose at which lipid levels in the blood can be changed, but that would not contribute to weight gain as fats and proteins also contribute.
The semen of the participants was examined at the beginning and end of the experiment lasted 12 weeks and the experts found no significant changes in body mass index, weight or activity level in both groups.
However, they found that they had consumed nuts had significantly increased levels of omega 6 and omega 3 fatty acids had an improvement in vitality, movement and morphology of their sperm, while the other group experienced changes.