[Avodah] donating blood

[Michael Kopinsky]

On 3/19/07, M Cohen <mcohen at touchlogic.com> wrote:
> I have heard others matir based on the assumption that one c/ consider it
> the same as hakazas dam (which the Gemara understands to be a health benefit
> for us)
>
This is not the Gemara's evaluation, but that of all "scientists"/doctors
of that era.  The assumed health benefit of hakazas dam (aka
blood-letting) was because a feverish patient had an excess of red bile,
and they had to let it out by bleeding.  Many patients died from such
treatment.  ("Hmmm, his face is red, I think we should slit his
wrists...")  While donating blood may be healthy (every blood donation
organization will claim it is), it is not for the reason the gemara thinks
it's healthy.

The last time I was at a blood drive, someone put a sign on the door
quoting the SA who says (and I misquote) "Hanichnas l'hakiz dam yomar Yehi
ratzon sheyihyeh l'refuah..."  That sign was a clear illustration of the
dangers of reading SA without any knowledge of history, and did not stay
up for very long. (I think I put it in sheimos.)