Friday, April 18, 2008

Too Little of 1 Vitamin Hurts Sperm

Men: If you want to father a child someday, you had better eat foods rich in folate now. Without this important nutrient, there is a far higher risk that your sperm will contain either too few or too many chromosomes, according to researchers from the University of California, Berkeley. Such sperm are more likely to lead to birth defects and miscarriages.

The health benefits of folate for women in their childbearing years have long been known. Too little folate in the diet causes birth defects, such as spina bifida and miscarriages. But until now, it was not known that it also affected men, reports HealthDay News.

What is folate? It's one of the B vitamins that is found naturally in spinach, asparagus, chickpeas and lentils. In addition, many foods, such as bread, cereal, rice and pasta, have been fortified with folate.

A man's sperm has 23 pairs of chromosomes. Normally there is one set of each, but sometimes a man may have two pairs of a particular chromosome or none at all. "We looked at sperm to find different kinds of genetic abnormalities," lead researcher Brenda Eskenazi, a professor of maternal and child health and epidemiology and director of the Center for Children's Environmental Health at Berkeley's School of Public Health, told HealthDay News. "The abnormalities we looked at here were having too few or too many chromosomes." When a normal egg is fertilized with an abnormal sperm, it can result in a birth defect, such as Down's syndrome, or increase the risk for miscarriage.

The study: The team looked at three specific chromosomes: X, Y and 21, and they analyzed the sperm from 89 healthy men. Each man was asked about how much zinc, folate, vitamin C, vitamin E and beta-carotene he consumed.

The results: Men who consumed the most folate had the lowest incidence of sperm abnormalities. Specifically, these men had a 20 percent to 30 percent lower frequency of several types of sperm abnormalities, compared with men who consumed less 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," Eskenazi explained to HealthDay News.

The takeaway: This is the first study to suggest that a father's diet may play a role after conception in the development of a healthy fetus. While the link is not conclusive, Eskenazi advises men who are thinking about becoming fathers to increase their folate intake, which can be done by eating more folate-rich foods or taking a vitamin supplement./p>

The study findings were published in the journal Human Reproduction.

--From the Editors at Netscape