We have known for some time that adequate folate (vitamin B9) in women’s diets can protect against miscarriage and birth defects in their babies, but a new animal study suggests that a father’s folate levels may be just as important. The research from Canada’s McGill University concluded that men eating high-fat, fast food diets or who are obese may not be able to use or metabolize folate in the same way as those with optimal levels of the vitamin. Working with mice, the researchers compared the offspring of fathers with insufficient folate in their diets with the offspring of fathers whose diets contained sufficient folate levels. They observed that a folate deficiency in the male mice was associated with an almost 30 percent increase in birth defects of various kinds in their offspring, compared to the offspring of fathers with diets containing adequate folate. Foods containing folate include spinach, green vegetables and beans as well as fortified products such as orange juice, baked goods, and cereals. Other natural sources of folate include asparagus, bananas, melons, lemons, legumes, yeast, and mushrooms.
Sarah Kimmins et al, "Low paternal dietary folate alters the mouse sperm epigenome and is associated with negative pregnancy outcomes," Nature Communications 2013; 4 DOI: 10.1038/ncomms3889