|
Iron is potentially
toxic because it serves as a catalyst in oxidation-reduction
reactions. Also, because the human body has a limited capacity
to excrete iron, it can build up in the body. Awareness of
the potential harm of iron stores in the body has increased
as animal and tissue studies have shown that large amounts
of iron can encourage increased rates of tumor growth, and
have found evidence of peroxidation induced by iron.
In one study of
men, those with serum ferritin (SF), an acute phase reactant
protein used to measure iron in the body, concentrations of
greater than 200 µg/L had an over twofold increase in
acute myocardial infarction than men with SF concentrations
below 200 µg/L. While other studies did not reflect
these findings, researchers suggest that increased SF concentrations
may not reflect increased iron stores, but may result from
infections associated with coronary heart disease.
Most studies to
date have been conducted in men, who tend to have higher iron
stores than women. Few studies have been conducted to determine
an association between iron stores and risk of cardiovascular
disease (CVD) in women of reproductive age. One recent study
examined this association among relatively healthy, non-pregnant
women aged 20 to 49 years. Data from a survey conducted from
1988 to 1994 were used to examine the relation between SF
concentration and CVD risk factors including body mass index
(BMI), total cholesterol, triacylglycerol, HDL cholesterol,
plasma glucose, and blood pressure. Results indicated that
SF was strongly correlated with total body iron stores, which
combines hemoglobin, serum transferrin, and ferritin. Researchers
say that these findings suggest that CVD risk factors are
positively associated with iron stores in women of this age
group.
American
Journal Clinical Nutrition December 2002 76;1256-1260
| 