Issue date:
July 3-5, 1998
The two faces of iron How much iron you need depends on your sex, age, diet and
genes.
In this article:
 Too little iron?
Too much iron?
This week's recipe:
Spinach Pesto Dip
HIGH IRON FOODS
 High in iron: liver, beef, ham, brewer's yeast,
legumes, lima beans, kidney beans, dark green leafy vegetables, dried
fruits (apricots, peaches, raisins, prunes), sardines, potato skin,
fortified cereals. Food has two forms of iron: heme and non-heme. You
absorb up to 30 percent of heme iron, found only in animal tissues
(meat, poultry and fish). You absorb 2-10 percent of non-heme iron,
found in plant foods as well as meat. Eating meat generally boosts body
iron far more than eating non-heme iron. What boosts iron absorption most: meat, iron
supplements, alcohol and foods high in vitamin C, according to new
research at Tufts University. Vegetable iron and vitamin C supplements
did not boost iron. What blocks iron absorption: coffee and tea taken
with meals. Cooking: Iron or stainless steel cookware transfers
iron into food, especially acidic food such as tomatoes. One classic
study found that spaghetti sauce had almost 30 times as much iron when
cooked in an iron pot than in a glass pot.
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 o you get too much or too little iron? Either can be
exceedingly dangerous. Here is the latest research on this vital
nutrient found in foods including spinach and shrimp.
Hazard 1: Too little iron Iron deficiency is America's most common nutritional problem,
notably for women and children. Low iron causes anemia and a breakdown
in vital functions leading to disease, premature birth, low mental
performance and death. Nearly 8 million young women (9-11 percent) and
750,000 toddlers (9 percent) are deficient in iron, according to a new
report by the federal Centers for Disease Control and Prevention.What you should do:
-- If you're an adolescent girl or a woman of childbearing
age, you are extremely vulnerable to iron deficiency because of the
monthly excretion of iron during menstruation. Eat foods rich in iron
and vitamin C. As insurance, take a multivitamin-mineral supplement with
the RDA of 15 milligrams of iron. Women of childbearing age should be
screened for iron deficiency, says the CDC.
-- If you are pregnant, check with your doctor about prenatal
vitamins. Take a low-dose iron supplement and eat iron-rich foods to
supply 30mg iron per day. Insufficient iron triples the likelihood of
low-birth-weight infants and doubles premature births.
-- If you have a baby, breast-feeding is the best guarantee
of adequate iron. If you don't breast-feed, use iron-fortified formula.
You can introduce iron-rich foods at 4 to 6 months. Caution: Primarily
feeding cow's or goat's milk before age 1 and drinking 3 or more cups of
milk a day from age 1 to 5 may promote iron deficiency and intestinal
bleeding. Deficiency in babies may cause irreversible motor, mental and
social abnormalities.
Hazard 2: Too much iron Accumulating, but controversial, evidence suggests that excess
iron can promote heart disease, diabetes, cancer and general aging.The latest: A 1997 study by neurologists at Innsbruck University
Clinic in Austria showed that men and women with the highest blood
ferritin (a form of iron) had the worst progression of artery clogging
over five years. When body stores of iron were reduced, heart disease
risk declined. The theory is that excess iron generates "free radical" chemicals
that damage cells and encourage a build-up of bad LDL cholesterol. Too
much iron, primarily in red meat, may promote cancer, notably colon
cancer, says recent research. Once metabolized, iron is not readily excreted (except by bleeding)
and can build up in tissue. What you should do:
-- If you're male or a postmenopausal woman, skip iron
supplements. Teenage boys need less iron than girls, and iron deficiency
is uncommon in boys. After age 18, men should not regularly take iron
supplements, warns leading iron researcher Jerome Sullivan, a
pathologist at the VA Medical Center in Charleston, S.C.
Photo Credit: KAREN SCHULD FOR USA WEEKEND
An ironclad recipe: SPINACH PESTO DIP
1 cup fat-free cottage cheese
1 firmly packed cup fresh spinach
1/3 firmly packed cup fresh basil
1/4 tsp. salt or to taste
1/2 tsp. Dijon mustard Process until smooth in a blender or food processor. Serve with
apple and pear wedges, cauliflower, broccoli, shrimp.
Makes 1 1/4 cups. Per tablespoon: 9 calories, 1.5g protein, 0g fat, 1g carbohydrates,
0.3g fiber, 69mg sodium, 0.3mg iron.
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SCIENTIFIC SOURCES FOR THIS COLUMN (7/5/98)
Primary source
Centers for Disease Control (CDC): Recommendations to Prevent and Control Iron Deficiency in the United States. Morbidity and Mortality Weekly Report (MWR), April 3, 1998, vol. 47. No. RR-3
Anemia
Looker AC, et al JAMA 1997;277:973-6
Iron and heart disease risk
Kiechl S, et al. Circulation 1997 Nov 18; 96(10): 3300-7
Too much iron promotes cancer
J National Cancer Institute 1994;86:455-460 and Int J Cancer 1994;56:364-369
If you're pregnant
School T, et al. Am J Clin Nutrition 1992;55985-988
What boosts iron absorption
Fleming DJ, et al. Am. Journal of Clinical Nutrition, April 1998, volaume 67 (4): 722-33
Coffee/tea blocks absorption
Tufts newsletter, Sept. 1997
Iron cookware
Jean Carper's Total Nutrition Guide, Bantam; p. 173
Stainless steel cookware
Park J, et al. J Am Diet Assoc 1997 Jun; 97 (6): 659- 61
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