Eating nuts significantly increases the quality of a man's sperm , a study has found
A trial found that nuts improve sperm count, vitality, swimming ability and shape - all factors that influence fertility
Nuts are rich in omega-3 fatty acids, antioxidants and folate, which in other studies have also been found to benefit sperm
For the 14-week study, 119 healthy young men aged 18 to 35 were randomly assigned to two groups
One ate a normal western diet, while the other consumed the same diet with 60 grams per day of mixed almonds, hazelnuts and walnuts
Comparing the two groups showed that men who had nuts added to their diet had a 16% higher sperm count, while their sperm vitality was improved by 4%, motility - swimming ability - by 6% and morphology (shape) by 1%
Men in the nut group also showed significantly reduced levels of sperm DNA fragmentation, which is closely linked to male infertility
The Spanish authors said the study results were not on their own enough to justify urging men to eat nuts if they want to conceive
But lead researcher Dr Albert Salas-Huetos, from the University Rovira i Virgili in Reus, said: "Evidence is accumulating in the literature that healthy lifestyle changes such as following a healthy dietary pattern might help conception - and of course, nuts are a key component of a Mediterranean healthy diet
” The findings were presented at the annual meeting of the European Society of Human Reproduction and Embryology (Eshre) taking place in Barcelona, Spain
A major study last year reported a significant general decline in sperm counts in North America, Europe, Australia and New Zealand between 1973 and 2011
The analysis of semen samples from more than 40,000 men showed that over this period, sperm counts fell by about 1
6% per year on average. British expert Allan Pacey, Professor of Andrology at the University of Sheffield, said: "There have been many studies showing that nutritional supplements (or diets) can influence sperm quality
For example there is quite a lot of data showing that men on 'good' diets (ie lots of fruit and veg) generally have better sperm quality than men on 'poor' diets (beef burgers and chips)
"This is generally put down to the fact that the former have a better micronutrient intake and more antioxidants than the latter group
However, I suspect that there isn't just one thing which causes the effect. "Therefore, with regard to this study, I am not surprised that a diet rich in nuts is associated with better sperm
” He added that a potential flaw in the study was that it was impossible to eat nuts "blind"
Trial participants who knew they were eating nuts might have changed other aspects of their lifestyle, which could have skewed the results