If you’re on the baby-making trail, stop the press, there’s a new sperm superfood in town. It’s walnuts.
Two separate studies have confirmed that walnuts are in fact, the nuts that are good for…. your nuts! (Okay, no more puns we promise. This is serious science.)
Two studies, one on men and one on mice have both demonstrated that walnuts can increase sperm quality by reducing lipid peroxidation, a process that can damage sperm cells. If you’re wondering how walnuts can do this its because they are the only tree nut that contains polyunsaturated fatty acids (PUFAs) which is actually the same material that sperm membranes are made from!
The preliminary research into sperm and walnuts began in 2012 (on men) and demonstrated that eating 75 grams of walnuts per day improved sperm vitality, motility and morphology in men who added walnuts to their diet compared to men who did not add walnuts. Healthy young men consumed their usual Western-style diet throughout the study and participated in monthly calls to share their dietary intake with the researchers. This research, led by Wendie A. Robbins was the basis for the expanded 2016 study which has announced its results this month.
The current study (conducted on mice) supports previous research that walnuts provide key nutrients that may be essential for sperm function. Specifically, researchers found significant improvements in sperm motility and morphology when the subjects diet contained 19.6% of calories from walnuts (equivalent to about 1/3 cup per day in humans). The quality of semen is generally determined on the combination of sperm motility (movement) and morphology (form) so increases in both can be considered an improvement in the male subject’s overall fertility.
“This animal research sheds light on how walnuts may improve sperm quality and is a great follow up to our human study that showed what effect walnuts may have,” says Dr. Robbins. “Studies that look at the factors underlying sperm quality improvements are very valuable for advancing research on this important topic.”
Animal research is generally provided as investigatory background and used to inform future studies needed to understand the effect on humans. The next step in understand just what walnuts do for men’s swimmers is a larger and longer-term study, as well as studies in more diverse male populations.
If you’re on the baby-making trail you might like to consider throwing some walnuts into your guy’s diet – like you needed an excuse to make some dark chocolate and walnut brownies anyway, right?
REFERENCES: Coffua LS, Martin-DeLeon PA. Effectiveness of a walnut-enriched diet on murine sperm: involvement of reduced peroxidative damage. Heliyon. 2017;3(2).
Robbins WA, Xun L, FitzGerald LZ, et al. Walnuts improve semen quality in men consuming a Western-style diet: randomized control dietary intervention trial. Biol Reprod. 2012;87(4):101.