|
|
Iron Overload |
Iron Overload
|
|
IRON OVERLOAD, OR MEAT OVERLOAD?
Too much blood iron has
been associated with an increase in heart disease. (1) On the other hand, a study published in the New England Journal of Medicine (2) by the National Center for
Health Statistics and Centers for Disease Control "reported that high transferrin saturation levels are not associated with an
increased risk of cardiovascular heart disease or myocardial infarction. On
the contrary, it was found that there is an inverse association of iron
stores with overall mortality and with mortality from cardiovascular
disease." (3)
In other words, high iron
does not cause cardiovascular disease, but low iron actually might. Health is
somewhere in the middle.
Twenty years ago, always
a shameless promoter of vegetarianism, I taught my clinical nutrition
students that there were two types of dietary iron: heme, and non-heme. That
basically means "blood," and "non-blood." Heme iron is
from meat.
Your body can soak up and
accumulate excessive heme iron even if it already has plenty of iron on hand.
But the really good news
is that your body has an automatic shut-off system to limit its absorption of
non-heme, or vegetarian, iron. Yes, this includes practically all iron
supplements on Earth (and those that may someday be made from meteors as
well).
Do I think you should
take an iron supplement, or a multiple vitamin containing iron? If you are a
child, yes. Iron deficiency remains a major public health problem for kids,
because they are making lots of blood as they grow. If you are a reproductive
aged female, yes again. Women lose about a half a cup of blood in every
menstrual cycle. That's like giving a unit of blood three times a year, ladies.
But this is no reason to
stuff women and children with the muscles of dead animals. A simple, cheap
multivitamin with iron will do the trick and save a cow. Vegetarianism (or in my personal opinion, what I call
"near-vegetarianism") has always been a good idea. Now it is better
than ever.
For men, iron
supplementation is generally unnecessary. For heme-heavy "meat and
potatoes men," it is positively a bad idea. Guys, if you give blood a
lot, persistently do excessively heavy exercise, or lose blood from injury,
take any average-dose iron supplement for a while.
Caution: These above comments, while valid for the great majority of people, do not apply to persons with hereditary hemochromatosis, which is a severe iron-buildup problem. Next time you have your blood checked, you can bring this up with your doctor of choice. References: 1. Ascherio A et al. Dietary iron intake and risk of coronary heart disease among men. Circulation 1994; 89:969-74. 2.
3. Carl Germano, M.A., R.D. Iron status and cardiovascular
heart disease.
HEMOCHROMATOSIS AND VITAMIN C MEGA-DOSIS:Gert Schuitemaker,
PhD writes:
“Hemochromatosis (HC) is underdiagnosed and should get more attention. We should
also take into consideration its relationship to high dosages of vitamin C. I
looked at your website (as I often do when I need some clinical practical
data), but you do not pay much attention to it. Dr. Thomas Levy in his book (http://www.doctoryourself.com/levy.html
) uses the term 'unlikely', but cannot be 'ruled out'. No studies are
available on the subject and - until then - high C users should probably
include at least an annual check on ferritin and iron. Do you consider HC a
non-issue?”
Good topic and a good
question. A known hemochromatosis (HC) patient
should not take megadoses of C. As for the rest of the population, I
recommend a low heme-iron diet, which is a low-meat or meatless diet. Vegetarian
diet provides non-heme iron, and even with mega-C, there seems to be a normal
iron absorption shut-off. (1) I think excess dietary heme iron may be
the real problem, not vitamin C. The body can relatively easily absorb more
heme (meat) iron than it needs. When and if vitamin C has a negative effect
in HC patients, it is probably due to release of stored iron, not new
absorption. (2)
In my opinion, one should
beware the questionable work of outspokenly anti-ascorbate hematologist
Victor Herbert, the voice behind claims that vitamin C is a public problem
due to looming dangers of iron overload. Herbert's papers grossly overstate a
statistically slight danger. There are no deaths per year from vitamin C; by
Herbert's logic, hundreds if not thousands of C users should be dropping dead
from HC. Herbert was the author of the “vitamin C destroys B-12 myth,”
which has been proven to be unfounded.
I append a comment by Dr
Steve Hickey, a vitamin C expert at U Manchester, and author of Ascorbate: The Science of Vitamin C (http://www.doctoryourself.com/news/v5n2.txt
):
“There is a
theoretical danger but the actual reports are sparse and unclear. I expect
that if vitamin C really did have such a side-effect, its detractors would
have had a field day. Having read much of the available evidence, I consider
the benefits of high dose vitamin C to exceed greatly any (largely
theoretical) side-effects.”
References:
1) Bendich
A, Cohen M. Toxicol Lett.
1990 Apr;51(2):189-201. Ascorbic acid safety:
analysis of factors affecting iron absorption. “Three parameters
associated with iron absorption were identified: (1) a relatively shallow
slope for the dose-response curve relating ascorbic acid dosage (1-1000 mg)
and percent iron absorption; (2) no significant effect of ascorbic acid on
the absorption of high (60 mg) iron doses; and (3) an inverse relationship
between iron absorption and plasma transferrin
saturation. Ascorbic acid did not increase the incidence of 'high' iron
absorbers (greater than 2 SD from population mean) above control levels;
limited data for ascorbic acid doses greater than 100 mg/d indicated no
change in the distribution of iron absorption values.” PMID: 2184546
2) Rowbotham
B, Roeser HP. Aust N Z J
Med. 1984 Oct;14(5):667-9. Iron overload associated
with congenital pyruvate kinase
deficiency and high dose ascorbic acid ingestion. PMID: 6597712
Andrew Saul is the author of the books FIRE
YOUR DOCTOR! How to be Independently Healthy (reader reviews at http://www.doctoryourself.com/review.html
) and DOCTOR YOURSELF: Natural Healing that Works. (reviewed at http://www.doctoryourself.com/saulbooks.html
)
For ordering information, Click here
This page and its content are
copyright © 2010 and previous years by Andrew W. Saul.
|
|
|
AN IMPORTANT NOTE: This page is not in any way offered as prescription, diagnosis nor treatment for any disease, illness, infirmity or physical condition. Any form of self-treatment or alternative health program necessarily must involve an individual's acceptance of some risk, and no one should assume otherwise. Persons needing medical care should obtain it from a physician. Consult your doctor before making any health decision. Neither the author nor the webmaster has authorized the use of their names or the use of any material contained within in connection with the sale, promotion or advertising of any product or apparatus. Single-copy reproduction for individual, non-commercial use is permitted providing no alterations of content are made, and credit is given. | ||
|
|
| Home | Order my Books | About the Author | Contact Us | Webmaster | |