Researchers at the University of California, Berkeley said that men having low levels of folate are at risk of having sperm with either too less or too much chromosomes. Both of these conditions are not desirable because they give rise to genetic abnormalities in children.

The researchers obtained sperm samples from 89 healthy, non-smoking men and analyzed the same. The men were questioned about their dietary habits, mainly related to consumption of diets rich in zinc, folate, vitamin C, vitamin E and beta carotene.

Reporting in the journal Human Reproduction, the scientists said the men who had high levels of folate had a 20 to 30 percent lesser degree of sperm abnormalities as compared to men who had low levels of folate.

"We saw an association between [male] folate intake and how many abnormal sperm there were, in terms of the chromosome number for these three different chromosomes," said lead researcher Brenda Eskenazi, a professor of maternal and child health and epidemiology and director of the Center for Children's Environmental Health.

Generally 4 percent of all human sperm has varying amount of chromosomes; a condition called as aneuploidy. The latter has been implicated in miscarriages as well as development of Down's syndrome, Turner's syndrome and Klinefelter's syndrome.

Folate is found in high levels in green leafy vegetables, fruits, beans, chickpeas and lentils. In the US and UK bread is fortified with folate to avoid birth defects. While the above study is in no way conclusive, it may be advisable for men planning parenthood to increase their intake of folate.