Iron carries oxygen in your blood and is a critical component of many enzymes that are critical for health. Polyphenols and other compounds in coffee and tea interfere with the absorption of iron in your intestines. Avoid taking any supplements containing iron with coffee or tea. Don't drink coffee or tea with iron-rich foods if you are deficient in iron or have a high dietary need.
Iron in the Body
Iron is present in two forms in both the body and foods: heme and nonheme iron. Heme iron is a component in hemoglobin, a protein that transports oxygen in the blood. Nonheme iron is found free or integrated into an enzyme that performs biochemical reactions in your body. Heme iron is found in beef, chicken, pork, fish and clams. Nonheme iron is found in beans, spinach and grains.
Coffee and Tea Polyphenols
The rich flavors and health properties found in coffee and teas are due to polyphenols and other chemical compounds extracted during brewing. These chemicals inhibit the absorption of iron into your body, especially nonheme iron. Calcium and some chemicals found in legumes and whole grains can also greatly decrease the absorption of nonheme iron, raising the risk of developing iron deficiency.
Iron Deficiency
According to the World Health Organization, iron deficiency is the most common nutritional disorder in the world. Iron deficiency can develop quickly after blood loss or gradually when dietary intake or absorption is too low. It is also important to have adequate levels of vitamin A to use iron in the body. Signs of iron deficiency include fatigue, decreased cognitive performance, irregular body temperature, decreased immune function and a swollen tongue.
Intake of Iron
It is important to obtain iron from easily absorbed sources, such as meats, or to eat foods that improve the absorption of nonheme iron. Protein and vitamin C can improve the absorption of nonheme iron. The National Institutes of Health recommends 7 to 11 mg of iron per day, with pregnant or menstruating women having a higher requirement. You can take iron supplements, but do not take them in high amounts or for prolonged periods to avoid overloading your system. Never take more than 40 mg per day of iron, NIH advises.
References
- "Journal of Agricultural and Food Chemistry"; Polyphenolic Chemistry of Tea and Coffee: a Century of Progress; Y. Wang, et al.; September 2009
- "The American Journal of Clinical Nutrition"; Inhibition of Food Iron Absorption by Coffee; T.A. Morck, et al.; March 1983
- Office of Dietary Supplements: Iron Fact Sheet
Member Comments