[net.cooks] How much Vitamin A is too much? That's A, not C this time

werner@aecom.UUCP (01/14/86)

> Regarding the fat soluable vitamins (eg. A, D, E), there is, again, a
> great difference between a natural and a synthetic vitamin (even excluding
> the left- vs. right-handed differences).  It is possible to get an over-
> dose of a synthetic fat-soluable vitamin.  Indeed, the FDA, for a long
> time, limited the amount of Vitamin A in a single tablet.  Yet, there is
> only one known case of Vitamin A toxicity with natural Vitamin A: someone
> was stranded in Alaska, resorted to a diet of polar bear liver for a few
> weeks, and had a slight case.
> 
> Alan M. Marcum

	Actually, there are several cases of Vitamin A toxicity from Bear
Livers. Hunters actually dying after a post-kill feast.  Its not epidemic
or anything, but it exists in a far more mundane manner than Alan's scenario.
	The myth that "natural" and "synthetic" vitamins differ in anything
besides concentration and dose is one of the great canards of the 20th Century.
It is repeated by vitamin salesman, and the well-intentioned misinformed, but
it just ain't so.
-- 

				Craig Werner
				!philabs!aecom!werner
  "Sometimes you have to run as fast as you can just to stay in the same place."

hollombe@ttidcc.UUCP (The Polymath) (01/15/86)

In article <2193@aecom.UUCP> werner@aecom.UUCP (Craig Werner) writes:
>	The myth that "natural" and "synthetic" vitamins differ in anything
>besides concentration and dose is one of the great canards of the 20th Century.
>It is repeated by vitamin salesman, and the well-intentioned misinformed, but
>it just ain't so.

I may be in the misinformed category.  My understanding is  that  "natural"
and  "synthetic"  vitamins  are  chemically  equal.   However,  the  body's
absorption and usage of vitamins depends on the  conditions  they're  taken
under.  Vitamins  in food are accompanied by all kinds of other stuff which
interacts with them and the body to influence their action and  absorption.
Taking  vitamin  pills ("natural" or "synthetic") on an empty stomach isn't
nearly as effective.

My solution:  I buy the cheapest vitamin supplement pills and take them with
	      meals.  What the heck -- can't hurt.

>  "Sometimes you have to run as fast as you can just to stay in the same place."

Been doing that for years ...

-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
The Polymath (aka: Jerry Hollombe)
Citicorp(+)TTI
3100 Ocean Park Blvd.             Geniuses are people so lazy they
Santa Monica, CA  90405           do everything right the first time.
(213) 450-9111, ext. 2483
{philabs,randvax,trwrb,vortex}!ttidca!ttidcc!hollombe

avinash@ubvax.UUCP (Avinash Marathe) (01/17/86)

In article <3131@sun.UUCP> Alan Marcum writes:
>> Regarding the fat soluable vitamins (eg. A, D, E), there is, again, a
>> great difference between a natural and a synthetic vitamin (even excluding
>> the left- vs. right-handed differences).  It is possible to get an over-
>> dose of a synthetic fat-soluable vitamin.  Indeed, the FDA, for a long
>> time, limited the amount of Vitamin A in a single tablet.  Yet, there is
>> only one known case of Vitamin A toxicity with natural Vitamin A: someone
>> was stranded in Alaska, resorted to a diet of polar bear liver for a few
>> weeks, and had a slight case.
>> 
>> Alan M. Marcum

To which Craig Werner responds:
>
>	Actually, there are several cases of Vitamin A toxicity from Bear
>Livers. Hunters actually dying after a post-kill feast.  Its not epidemic
>or anything, but it exists in a far more mundane manner than Alan's scenario.
>-- 
>				Craig Werner


There is no way one can get Vitamin A toxicity from eating Vitamin A from
vegetable sources.  Actually, vegetable sources do not contain Vitamin A
but the precursor to Vitamin A called beta-carotene.  The liver converts
as much beta-carotene as it needs into Vitamin A and the rest is excreted.
Also beta-carotene is water soluble unlike Vitamin A.  Beta-carotene is 
what gives carrots, melons, and squashes their orange/yellow color.

One can definitely get vitamin A toxicity from animal or synthetic sources,
because Vitamin A exists as Vitamin A in these sources.

Avinash Marathe
{ihnp4,decwrl,allegra}!amd!ubvax!avinash