There's a lot of pressure on pregnant and and trying-to-get-pregnant women to do the right things: get the right vitamins, eat the right diet, restrain from the right vices at just the right time. But just as dads are taking on larger roles in the home, there is a growing body of research that suggests that men should be paying attention to their habits in the run-up to pregnancy, too—that males' choices can also affect a child's biological development.
A man who is obese, who smokes or drinks or who is exposed to toxic industrial chemicals can affect pregnancy rates and child development. And a new study shows that, at least in mice (which are pretty similar to humans for stuff like this), nutrient shortages in fathers can affect the rate of birth defects in their babies.
In an experiment where some male mice were fed a diet without enough folate, scientists found that their babies were more prone to birth defects. Sarah Kimmins, one of the researchers behing the study, told the CBC:
There's a perception that's no longer true, that really needs to be challenged, that the father can do whatever he wants in terms of what he eats, what kind of lifestyle he lives, whether he takes drugs or not, and this isn't going to affect whether he has a healthy child or not," she said.
"Our research really shows that this isn't the case — men really need to think carefully about the life they're living because there is a potential for an impact on the offspring.
Most men who eat normal diets should have folate levels that are fine. But, if a man is malnourished, he may not be getting enough. Or, inversely, if a man is obese, it can affect how folate is processed, meaning that even if he has enough, it may not be doing its job properly.
The folate shortages matter, says the Los Angeles Times, because it affects the proper functioning of the male mouse's sperm. “As a result, those fathers apparently pass along an embedded “environmental memory” that affects how the genetic code plays out for the baby both in the womb and during a lifetime.”
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