Approximately 70 million couples experience infertility worldwide, with 30 to 50 percent of these cases attributable to the male partner. An increasing western style diet have been shown in some studies to affect sperm quality. Dr. Wendie Robbins and her colleagues at the University of California, decided to investigate whether increasing polyunsaturated fatty acids (PUFAs), which are critical for sperm maturation would increase sperm quality in men consuming a Western-style diet.
117 healthy men between the ages of 21 and 35 were selected. They were split into two groups: one (58 men) who would avoid eating tree nuts and another (59 men) who would eat 75 grams of walnuts per day. The men's semen quality was analyzed before and after the experiment. The findings showed that after 12 weeks, the men consuming walnuts had significantly increased levels of omega-6 and omega-3 fatty acids and experienced improvement in sperm vitality, motility, and morphology. Those eating walnuts also had fewer chromosomal abnormalities in their sperm following the walnut dietary intervention. The other group, on the other hand, experienced no changes.
Even though, this study have shown that eating walnuts can positively affect a young men sperm, it does not show whether the benefits would apply to men with fertility problems
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