Male Fertility Gets Boost From Eating Walnuts
August 16, 2012

Male Fertility Gets Boost From Eating Walnuts

Connie K. Ho for — Your Universe Online

Researchers from the University of California, Los Angeles (UCLA) recently discovered that consuming 2.5 ounces of walnuts a day can heighten semen quality in young men.

The paper, published in a recent edition of Biology of Reproduction´s Papers-in-Press, included data that showed that 75 grams of walnuts per day could increase sperm motility, vitality, and morphology of men between the ages of 21 and 35.

The team of investigators decided to study the subject of male fertility and walnuts to determine if increasing polyunsaturated fatty acids (PUFAs) could affect sperm maturation and membrane function, which would then lead to increased sperm quality in men who practiced a Western-styled diet. In the Western-styled diet, many PUFAs have been found in fish and fish oil, flax seeds, and walnuts. Walnuts are also known to contain high amounts of a-linolenic acid (ALA), which is a natural plant source of omega-3.

In the study, 117 healthy male participants were selected and split into two groups; one group was prohibited from eating tree nuts, while the other group was required to eat 75 grams of walnuts each day. Past studies had demonstrated that 75 grams of walnut was the right amount to help blood lipid levels change, while not causing any weight gain in young men. The subjects were between the ages of 21 and 35 who consumed a Western-styled diet. The experiment was done over a 12-week period, with male semen quality analyzed before and after the experiment. The researchers looked at factors such as sperm chromosome abnormalities, motility, concentration, and vitality.

Based on the project, the team of investigators did not determine that there were any changes in activity level, body-mass index, or body weight. However, there was a boost in levels of omega-6 and omega-3 (ALA) fatty acids for men who ate walnuts. As well, they reported improvement in sperm vitality, motility, and morphology along with fewer chromosomal abnormalities. The control group did not show any significant changes in these various areas.

The scientists believe that the study could be of interest to 70 million couples who have issues related to infertility or subfertility. In 30 to 50 percent of these cases, the question of fertility is due to the male partner. Other studies have proposed that human semen quality has lowered in industrialized nations; the decline may be due to pollution, poor life style habits, or the Western-styled diet.

"I think this highlights how important dietary factors are in promoting fertility health," Dr. John Petrozza, director of the Massachusetts General Hospital Fertility Center, told WebMD.

Even with the improvements in the males who ate the 75 grams of Walnuts, researchers are still unsure if the benefits could be applied to young men who have fertility problems or if the consumption of walnuts can help boost fertility overall.

"This will come out with future papers. For now, the idea is to eat healthy with a varied diet," commented Petrozza in the WebMD article.

The study was funded by the California Walnut Commission.