The benefits and drawbacks of caffeinated and herbal tea

Whether it's caffeinated or herbal, tea is a tasty and satisfying drink. Read on to learn about some of the health benefits and drawbacks associated with tea.

• Tea leaves contain twice as much caffeine, weight for weight, as coffee beans do. But when measured by volume, tea has only half as much caffeine as coffee because tea is drunk weaker and coffee is more completely extracted from the grounds.
• 250 millilitres (one cup) of black or green tea contains 35 to 45 milligrams of caffeine.
• Tea may trigger a migraine headache in hypersensitive people; for others, it may alleviate headaches when taken with aspirin or similar painkillers.
• Theo­bro­mine, which is also found in tea, has effects similar to those of caffeine but milder.

The tannins in tea can cut iron absorption by more than 80 percent when tea is drunk with an iron-rich meal.

• Tea-drinking vegetarians are especially susceptible.
• Individuals with a tendency to anemia can drink citrus juice at mealtimes to promote iron absorption; squeezing a wedge of lemon or adding milk to tea also binds the tannins and partly blocks their effect on iron.
• Tea drinking between meals does not affect iron absorption.
• Young children should not drink tea, which can increase their risk of iron-deficiency anemia.
• In addition, tannins can stain natural teeth and dental work, and some mouthwashes may intensify the staining.

Tea, like coffee, has a diuretic effect, which increases the kidneys' output of urine.

• Excessive urination can upset the body's fluid and chemical balance by washing potassium from the body.

Many plants, especially herbs, can be brewed into teas, also called infusions or tisanes. Because most of them do not contain caffeine, they offer a pleasant alternative for people who prefer to avoid this stimulant.

• Some herbal teas aid the digestion, and their soothing warmth can promote relaxation at bedtime.
• Researchers have found that people who drink about a litre (four or five cups) of green tea daily are likely to improve their cholesterol levels.

Always choose herbs carefully. Although the herbs and spices used in herbal teas have been approved by government regulatory bodies for use as seasonings, a few herbs and spices are known to be unsafe when used medicinally.

• Nutmeg, for example, is harmless when used to flavour foods but can cause severe symptoms, in­cluding hallucinations, when brewed into a strong tea.
• Other herbs, such as oregano, have a stimulating effect and can cause wakefulness.
• Comfrey tea, if consumed regularly, is toxic to the liver.
• Scientific information is inconclusive regarding the safety of various herbs and herbal products during pregnancy and while breast-feeding.
• The herbal teas considered safe if used in moderation include citrus peel, ginger, lemon balm, orange peel and rose hip.
• It is wise for pregnant women to discuss use of these drinks with their healthcare provider.

Overall, tea is a delicious drink with many health benefits. However, you need to make sure you know exactly what herbs are in your tea to avoid some of the negative side effects.