Thursday, April 24, 2008

An Interesting Article, but it just doesn't make sense.

Apparently, a woman is more likely to conceive a male if she eats a high-calorie diet, yet a female if she eats low-fat this and skim that. It's really neat, and makes sense based on there being more girls born these days, but it's one of those cases where you really shouldn't take it seriously - because it's not her choice!

That is to say, it's not her body that chooses - sperm are made in the man with X or Y chromosomes, and whichever races first to the egg makes the kid. How on earth is a woman's diet supposed to determine that?



April 26, 2008 at 9:17 PM

But if, for example, the woman's diet affects the pH or something in her uterus, then say, XY sperm might swim faster and thus be more likely to reach the egg in a more acidic environment. Or something along those lines. I saw the same article, and that's the interpretation I got out of it anyway.


April 26, 2008 at 11:00 PM

But that's pretty intense.
I wonder if there's anything similar that would influence a man's sperm count...


April 26, 2008 at 11:15 PM

I know that heat can reduce a man's sperm count, e.g. hot tubs, saunas, even laptops. And XY sperm are in general slightly faster, which explains the approx 105 baby boys to 100 baby girls ratio in normal populations, because males have higher lifetime mortality, so the numbers even out around reproductive age.

I don't know of anything else that affects the relative proportions of XX and XY sperm though, although I think some pollutants might (heavy metals or something).