Too Much of a Good Thing

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Too Much of a Good Thing JoAnn Guest Dec 11, 2004 19:05 PST

 

http://www.askbillsardi.com/sdm.asp?pg=iron

 

From The June 2000 Issue of Nutrition Science News

Too Much of a Good Thing

by Bill Sardi

 

Recent studies reveal that blood donors exhibit lower rates of many

diseases and experience better than average health.

 

Additionally, the centuries-old practice of bloodletting is being

revived as a treatment for disorders such as heart disease, cancer and

Alzheimer's.1

Why would blood reduction improve health parameters? In part, because

blood removal helps to control

circulating iron levels.

 

Iron is an essential component of hemoglobin in red blood cells, is

associated with strength, and is required for oxygen transport, DNA

synthesis and other processes.

But it also has a destructive nature. In its free form, unbound from

hemoglobin or other binding proteins,

it accelerates 'oxidation' or " rusting " of body tissues.

 

Since iron-induced 'oxidation' worsens the course of virtually

every disease, iron control could be a universal approach to disease

prevention and therapy.

 

Whereas poor iron intake, or impaired absorption, may lead to

anemia, too much iron--iron overload--is even more problematic.

After full growth is achieved,at about age 18 or so, excess iron

accumulates in the blood of all humans at the rate of 1 mg per day.

 

About 80 percent of the body's iron stores are in the blood.

 

Women are less at risk for iron buildup than men because of the

blood they lose monthly during menstruation. As a result, women have

somewhere around half the circulating iron levels as men.

Their rates for heart disease,cancer and diabetes are also about half

those of males. Because men have no direct outlet for iron, by age 40

their iron levels are similar to those of a a postmenopausal 70 year old

woman

 

This amount of iron can lead to premature aging and diseases such as

arthritis, cancer, cataracts, diabetes,

osteoporosis, and retinal, liver and brain disorders.

Postmenopausal women, or women who have undergone early hysterectomy

in their 20s, 30s and early 40s,may experience similar problems.

 

Recognizing the Problem-

 

Iron overload hasn't gone completely unnoticed. There are a number

of books on the topic, but most are written for health professionals,

leaving the public largely unaware of the problem.

 

Also, some confusion exists regarding the role of iron in health and

disease.

 

First, there is a mistaken idea that the majority of the people

affected by iron overload diseases have the genetic form, called

hemochromatosis, which affects only about 1 million of the estimated 275

million Americans.

 

In fact, the potential threat of iron overload is universal. It comes

with advancing age and regardless of genetic factors.

 

Second, the emphasis on preventing anemia in children and

menstruating women has detracted attention from progressive iron buildup

in adult men and postmenopausal women.

 

Raymond Hohl, M.D., an assistant professor

of internal medicine and pharmacology at the University of Iowa in

Iowa City, says even chronic use of a baby aspirin may

in some cases " induce " iron-deficiency anemia.

 

By exercising, a person loses about 1 mg of iron through sweat.

 

Fasting and vegetarian diets, both of which promote longevity in animals

and humans, limit iron consumption because red meat contains the highly

absorbable heme iron. Whether or not related to iron consumption,

restricting red meat consumption has been shown in various studies to

reduce the risk of colon cancer.

 

Normal Iron Regulation-

In healthy individuals there is little if any unbound iron

circulating in the blood. In all disease states, however, unbound iron

(also called free iron) is released at sites of inflammation and can

spark uncontrolled " oxidation " .

 

Fortunately, there are numerous automatic mechanisms in the body

that help to control iron, many by chelation--compounds that bind to a

toxic substance (such as iron) and render it nontoxic or nonactive.

 

Albumin, a simple protein found in blood, acts as a chelator by loosely

binding to iron. Ferritin, produced the liver, is another iron-binding

protein.

 

Transferrin is a protein that chelates iron and totes it back to the

liver, where it is metabolized and excreted.

 

The liver produces lactoferrin, another iron chelator,

when challenged by infectious agents.

This is important because pathogenic organisms such as viruses,

bacteria and fungi require iron for growth.

 

Furthermore, as iron stores increase, the gastric absorption of iron

decreases.

So the body employs numerous mechanisms to control iron that are

activated when threatened by disease. However, these defensive

mechanisms can be overwhelmed.

 

Blood tests for iron levels (i.e., hemoglobin and ferritin levels

are checked for transferrin saturation percentages) are often useful,

but the results of these tests are confounded in states of prolonged

inflammation or disease.

 

A skilled hematologist is often the best professional from whom to

obtain personal information concerning blood iron levels.

 

Differentiating between anemia and iron overload can be difficult

because both conditions cause fatigue. One study at the Department of

Medicine, University of Western Ontario in Canada, found that iron

overload can produce a wide range of symptoms, such as joint pain

(particularly hip), unexplained gastric pain,

frequent infections, skin bronzing, elevated liver enzymes,

cessation of menstruation, hair loss and heart flutters (fibrillation).

 

Yet, of 410 iron-overload patients, 27 percent experienced no symptoms

whatsoever.

Common symptoms of iron-deficiency anemia are lowered resistance to

infections, fainting, breath holding, mental fatigue, sleepiness, cold

hands and feet, and cravings for ice, meat or tomatoes, all which are

more likely to occur among women.

 

Dietary Iron Control-

 

Various dietary practices can help control iron levels. In a

relatively shortperiod of time, dietary changes can result in anemia,

iron overload or an ideal state of iron control. Anemia can be induced

in about 120 days, while symptoms

of iron overload can come on in just 60 days.

 

Humans absorb only a fraction of the iron they consume, but there

are many controlling factors.

Iron absorption rates from food vary widely, from less than 1 percent

to nearly 100 percent. Cooks who use iron or stainless steel pots

increase the amount of iron they consume.

 

 

Olive oil and spices such as anise, caraway, cumin, licorice and mint

promote iron absorption, while antacids reduce availability.

 

Since dairy products contain lactoferrin, milk also inhibits the

absorption of iron.

 

Moderate alcohol consumption is unlikely to pose a problem with iron

absorption, but excessive amounts of alcohol is associated with iron

overload,particularly in adult males.

 

Vitamin C also increases iron absorption.

 

However, there is no evidence that vitamin C leads to iron overload.

Thus vitamin C should not be avoided for this reason, since studies show

high-dose vitamin C supplements

are associated with a decreased risk for heart disease, cancer,cataracts

and other disorders.

 

A vegetarian diet does not generally cause iron- deficiency anemia

because there is more vitamin C in plant-food diets,

which " enhances " absorption.

 

A 1982 human study was conducted to assess the effect of various

drinks on iron absorption. A subject ate a standard meal of a hamburger,

string beans, mashed potatoes and water.

 

When green tea was consumed rather of water, iron absorption was reduced

by 62 percent.

 

Coffee reduced iron absorption by 35 percent, whereas orange juice (as a

source of vitamin C) increased absorption by 85 percent. Contrary to

other studies, milk and beer had no significant effect.

 

Bioflavonoids (found in berries, coffee, green tea, pine bark,

quercetin and the rind of citrus fruits, particularly blueberry,

cranberry, elderberry and grape seed) and phytic acid (a component of

whole grains and seeds such as sesame) bind to iron and other minerals

in the gastric tract and help to limit iron availability.

 

If bioflavonoids and phytic acid haven't bound to minerals in the

digestive tract they will get into the bloodstream, where they can bind

to free iron, acting as blood-cleansing iron chelators.

 

Therefore, maximum iron chelation in the blood circulation is achieved

when these iron binders are consumed apart from meals.

 

 

Phytic acid--also called inositol hexaphosphate, or IP6--is

comprised of six phosphorus molecules and one molecule of inositol. It

has been mistakenly described for decades as an " anti-nutrient " because

it impairs mineral absorption.

 

However, in the 1980s food biochemist Ernst Graf, Ph.D.,

began to tout phytic acid for its beneficial antioxidant properties

achieved through mineral chelation.

Phytic acid in foods or bran should be distinguished from

supplemental phytic acid, which is derived from rice bran extract.

 

In foods, phytic acid binds to iron and other minerals in the digestive

tract and may interfere with mineral absorption.

 

As a purified extract of rice bran, taken between meals

so it will not bind to minerals in the digestive tract, phytic acid is

readily absorbed

into the bloodstream, where it acts as a potent mineral chelator.

 

Phytic acid binds to any free iron or other minerals (even heavy metals

such as mercury, lead and cadmium) in the blood, which are then

eliminated through the kidneys.

 

 

Phytic acid removes only excess or unbound minerals, not mineral

ions already attached to proteins.

 

Phytic acid is such a potent--but safe--iron and mineral chelator

that it may someday replace intravenous chelation therapy such as the

mineral- chelator EDTA or iron-binding drugs such as desferrioxamine

(Desferal).

 

Because of its ability to bind to iron and block iron-driven hydroxyl

radical generation (water-based) as well as suppress lipid

" peroxidation " (fat-based), phytic acid has been used successfully as an

antioxidant food preservative.

 

Phytic acid supplements should not be taken during pregnancy since

the developing fetus requires minerals for proper development.

 

Because aspirin causes a small loss of blood and consequently helps to

control iron, the simultaneous use of phytic acid with a daily aspirin

tablet is not advised.

 

A three-month course of phytic acid should achieve adequate iron

chelation, and prolonged daily supplementation may lead to

iron-deficiency anemia.

 

Anemic individuals who take phytic acid as a food supplement are likely

to feel weak shortly after consumption, whereas iron-overloaded

individuals are likely to feel increased energy.

 

For those at risk for iron overload, it may be wise to avoid iron in

multivitamins and shun fortified foods that provide more than 25

percent of the recommended daily intake for iron.

 

No doctor should prescribe iron tablets for patients who complain of

fatigue without blood tests and a thorough health history.

 

Iron-rich foods such as organic molasses may prevent

anemia and build strength during the growing years but in adulthood may

lead to iron overload among men and postmenopausal women.

 

Those individuals who learn how to achieve iron balance will maintain

the most desirable state of health throughout life.

 

 

 

Bill Sardi is a health journalist and consumer advocate in Diamond

Bar, Calif. He recently published The Iron Time Bomb (Bill Sardi, 1999).

 

 

References

 

1.Bonkovsky HL, et al. Iron in liver diseases other than

hemochromatosis. Semin Liver Dis 1996;16:65-82.

 

2. Gutteridge JMC, Halliwell B. Antioxidants in nutrition, health

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New York: Oxford University Press; 1994. p 24-39.

 

3. McCord JM. Iron, free radicals, and oxidative injury. Sem in Hem

1998;35:5-12.

 

4. Crawford RD. Proposed role for a combination of citric acid and

ascorbic

acid in the production of dietary iron overload: a fundamental cause

of

disease. Biochem Mol Med 1995;54:1-11.

 

5. Emery TF. Iron and your health. Boca Raton (FL): CRC Press; 1991.

p 1-13.

 

6.Arthur CK, Isbister JP. Iron deficiency. Drugs 1987;33:171-82.

 

7. Rider JA, et al. Double-blind comparison of effects of aspirin and

namoxyrate on pH of gastric secretions, fecal blood loss, serum iron

and

iron-binding capacity in normal volunteers. Curr Ther Res 1965;7:633-

8.

 

8. Bankhead C. In assessing anemia, doctors must decipher role of

iron

deficiency. Med Tribune Clin Focus 1997 Mar; 20:24.

 

9. Oberle S, et al. Aspirin increases ferritin synthesis in

endothelial cells:

a novel antioxidant pathway. Circ Res 1998;82:1016-20.

 

10. Vellar OD. Studies on sweat losses of nutrients. Scand J Clin

Lab Invest

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11. Kampman E, et al. Meat consumption, genetic susceptibility, and

colon

cancer risk. Cancer Epid Biomarker Prev 1999;8:15-24.

 

12. Griffiths, E. Iron and infection. New York: John Wiley &

Sons;1987. p 1-25.

 

13. Goldwasser P, Feldman J. Association of serum albumin and

mortality risk. J

Clin Epid 1997;50:693-703.

 

14. Aust SD. Ferritin as a source of iron and protection from iron-

induced

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15. Aisen P, Brown EB. The iron-binding function of transferrin in

iron

metabolism. Sem Hematol 1977;14:31-46.

 

16. Baker EN, et al. Three-dimensional structure of lactoferrin. Adv

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17. Hulten L, et al. Iron absorption from the whole diet in men: how

effective

is the regulation of iron absorption? Am J Clin Nut 1997;66:347-56.

 

18. Adams PC, et al. The relationship between iron overload,

clinical symptoms

and age in 410 persons with genetic hemochromatosis. Hepatology

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19. Marinella MA. Tomatophagia and iron-deficiency anemia. N Eng J

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20. Monsen ER. The ironies of iron. Am J Clin Nutr 1999;69:831-2.

 

21. Hurrell RF. Preventing iron deficiency through food

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22. Park J, Brittin HC. Increased iron content of food due to

stainless steel

cookware. J Am Diet Assoc 1997;97:659-61.

 

23. U.S. Agricultural Research Service, USDA Bulletin. 1998 Dec 23.

 

24. El-Shobaki FA, et al. The effect of some beverage extracts on

intestinal

iron absorption. Z Ernahrungswiss 1990;29:264-9.

 

25. Morris ER. An overview of current information on bioavailability

of dietary

iron to humans. Fed Proc 1983;42:1716-20.

 

26. Davidsson L, et al. Influence of ascorbic acid on iron

absorption from an

iron-fortified chocolate-flavored milk drink in Jamaican children.

Am J Clin

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27. Fletcher LM. Alcohol and iron: one glass of red or more? J

Gastro Hepatol

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28. Derman DP, et al. Importance of ascorbic acid in the absorption

of iron

from infant foods. Scand J Haematol 1980;25: 193-201.

 

29. Gerster H. High-dose vitamin C: a risk for persons with high

iron stores?

Int J Vitam Nutr Res 1999;69:67-82.

 

30. Craig WJ. Iron status of vegetarians. Am J Clin Nut 1994 May; 59

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Suppl):12335-7.

 

31. Hallberg L, Rossander L. Effect of different drinks on the

absorption of

non-heme iron from composite meals. Hum Nutr Appl Nutr 1982;36:116-

23.

 

32. Graf E, et al. Phytic acid--a natural antioxidant. J Biol Chem

1987;262:11647-50.

 

33. [No authors listed] Phytic acid: new doors open for a chelator.

Lancet 1987

Sept 19:2;2(8560):664-6.

 

34. Lee BJ, Hendricks DG. Phytic acid protective effect against beef

roundmuscle lipid peroxidation. J Food Sci 1995;60:241-4.

_________________

 

JoAnn Guest

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DietaryTi-

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