Black tea is a popular caffeinated beverage that may be enjoyed hot or cold. It is safe for most adults, provided that it is consumed in moderate amounts to avoid the side effects of excessive caffeine intake. However, people with iron deficiency or anemia may experience a worsening of symptoms after drinking black tea.
Drinking black tea alongside a meal containing iron decreases your body's ability to absorb iron from food. This is due to the presence of tannic acid in tea. Tannic acid and chemically-related plant chemicals known as polyphenols bind to the iron in food and sequester it. This is not usually a problem for most individuals. However, if your iron levels are low or if you belong to a group at risk for iron deficiency anemia, you should consider drinking tea between meals instead of alongside food.
Black tea blocks the absorption of iron from certain foods much more than others. Drinking tea with red meats, poultry or fish does not significantly decrease the amount of iron your body receives. These animal products contain the heme form of iron, which is easily absorbed by your body. In contrast, the non-heme iron in plant foods is more difficult for your body to use and more likely to be inhibited by black tea.
In contrast to the iron inhibiting foods, some foods actually enhance your body's ability to retrieve iron from heme and non-heme iron sources. Foods that are high in vitamin C help your body absorb more iron from food, so one effective method is to combine vitamin C-rich and iron-rich foods in meals. At breakfast, you can increase the amount of iron you get from fortified oatmeal by drinking a glass of orange juice with your meal. You can also add vitamin C-rich peppers to a salad made with iron-rich spinach and beans.
Other Iron Inhibitors
Calcium also inhibits iron absorption. If you are concerned about low iron levels, you should eat calcium-rich foods such as milk and other dairy products separately from iron sources. Likewise, if you are taking an iron supplement do not take a calcium supplement at the same time. Your doctor or pharmacist can help you determine an appropriate schedule for taking different supplements. Coffee, egg whites, soy protein and high fiber foods can also block iron uptake.