"Eat your veggies" is the message for men now that a new study concludes that eating high amounts of folate reduces chromosomal abnormalities in sperm.
Folate is a B vitamin found in leafy green vegetables and fortified cereal and folic acid is the synthetic version found in multivitamins.
Researchers estimate that between 1 per cent and 4 per cent of a healthy man's sperm has some kind of aneuploidy (where a chromosome has been gained or lost).
Just under 100 men were asked to outline their regular diet and their daily intake of zinc, folate, beta-carotene, vitamin E and vitamin C. The men who consumed the most folate had 20 per cent to 30 per cent lower frequency of aneupoloidy.
There was no connection between lower sperm abnormalities and the other vitamins.
A principal author of the study, Brenda Eskenazi, professor and director of the Centre for Children's Environmental Health at the School of Public Health at the University of California, Berkeley, cautioned: "This study cannot prove that high folate intake caused the lower sperm aneuploidy levels, only that there is an association... the results indicate the need for further research."
Women trying to get pregnant have long been told to increase their folate or folic acid intake to reduce the risk of birth defects in their babies. This is the first study to show that a man's diet may have an impact on the development of health sperm and, therefore, a healthy baby, said Eskanazi.
The current recommended daily intake (RDA) of folate for men over age 19 is 400 micrograms, and if other studies confirm these findings it may mean that men should increase their intake before trying to conceive.
The study, jointly conducted between the University of California, Berkeley, and the Lawrence Berkeley National Laboratory, will appear Thursday in the European reproductive medicine journal Human Reproduction.
