IU's (international units) and mcgs and mgs are not eqivalent. You are sort
of talking about apples and oranges here :-)
International Unit (I.U.)
"An internationally accepted amount of a substance.  Usually this form of
expressing QUANTITY is used for vitamins, and some hormones, enzymes and
biologicals such as vaccines.  These units are defined by the International
Conference for Unification of Formulae."
Taber's Med Dictionary.

So an I.U. for ANY substance equals what this body says an I.U. equals.  An
I.U. of a substance may be generally accepted as 400 mg of that substance or
4 mg of that substance or even 4 mcg of that substance, but it is INDIVIDUAL
for each substance measured in I.U.

400 I.U. a substance could be lethal if you gave 400 mg of that substance.

microgram (mcg or ug)  is  one thousandth of a milligram (mg) and
one-millionth part of a gram !

Hope this makes some sense.  Pat in SNJ

             ***********************************************

To temporarily stop your subscription: set lactnet nomail
To start it again: set lactnet mail (or digest)
To unsubscribe: unsubscribe lactnet
All commands go to [log in to unmask]

The LACTNET mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software together with L-Soft's LSMTP(R)
mailer for lightning fast mail delivery. For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html