About one in six couples are infertile, with 40 percent of that infertility due to factors from the male side. Male infertility is generally thought to be caused by inadequate quantity of sperm production, or compromised size and shape of the sperm itself.
But in potentially good news for couples struggling to become pregnant, a new study has found that eating two handfuls of walnuts a day improves sperm health in young men.
The study, published in the journal Biology of Reproduction, discovered that sperm shape, movement and vitality improved in men who added walnuts to their diet over 12 weeks.
This study included 117 men between the ages of 21 and 35. The participants were divided into two groups — one who consumed 2.6 ounces of whole-shelled walnuts along with their daily diet, and the other group who ate a regular diet while avoiding nuts altogether.
The lead author, professor Wendie Robbins from UCLA's Fielding School of Public Health, said, "We found a significant improvement in sperm parameters in the group that consumed the walnuts. The men who ate no tree nuts saw no change."
Sperm quality improved in terms of concentration, vitality, movement, shape and chromosome abnormalities.
The fatty acids, like omega-3, found in these nuts are thought to have improved sperm quality, although it is not known if this would help improve male fertility, signs are encouraging.
The researchers note that the next step is to work with couples experiencing infertility due to poor semen quality and then determine if adding walnuts to the diet results in better success of conception.