I'm not even sure if this claim is true, but...

This source states that

Caffeine gives both types of sperm a boost, but the Y-sperm would get a little more of a boost.

This article reinforces the quote. In fact, this "tip" can be seen all over the internet to preferentially conceive a male rather than a female.

My question is how. What is happening at the molecular to increase the overall mobility of sperm? It clearly wouldn't work as a neurotransmitter (as it "normally" works).

  • 2
    $\begingroup$ I also realize that this question could be formatted for Skeptics.SE. Feel free to edit the question so that it's more suited for this site. $\endgroup$ Commented Jun 4, 2012 at 19:57
  • $\begingroup$ This answer suggests that the "extra boost" could be due to all Y sperm being lighter and therefore perhaps faster than X sperm - regardless of caffeine consumption. $\endgroup$
    – Rory M
    Commented Jun 5, 2012 at 11:02
  • $\begingroup$ @RoryM I'm familiar with that, as the comments to this answer also suggest: biology.stackexchange.com/questions/1062/x-chromosome-weight $\endgroup$ Commented Jun 5, 2012 at 13:57
  • $\begingroup$ I'm more interested in the "boost" itself rather than the differential boost. $\endgroup$ Commented Jun 5, 2012 at 14:03
  • 1
    $\begingroup$ Ah it was that question I was trying to find earlier xD $\endgroup$
    – Rory M
    Commented Jun 5, 2012 at 14:36

1 Answer 1


The cell response for caffeine, is at the molecular level of RyR (Ryanodine receptor), and the main effect could be a temporal rise in Ca+2 cytosolic concentration, so it can change the electrical behavior for the whole cell, and then affect their mobility. But the main area for RyR research is at spermatogenesis, there are a lot of papers like this one, for that topic


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .