Are There Any Negative Reasons Not to Drink Green Tea?

The health benefits of green tea are already well-documented, and it seems as if more and more are being discovered every day. Most of the benefits are associated with the antioxidants in green tea, which boost immunity, lower cancer risk and help prevent stroke. But almost everything has at least some unwelcome side-effects, and this is also true of green tea, although the benefits far outweigh the negatives.

Caffeine

• Green tea contains caffeine. Generally a cup of green tea will give you about 30 to 60 milligrams of caffeine. This compares to 100 milligrams for a cup of coffee. But there are well documented side effects to drinking too much caffeine, first among them insomnia. You could also potentially suffer from excessive urination, stomach upsets or if you have a particular caffeine sensitivity, hives or other allergic reaction.

Effects in Pregnancy

• Pregnant and nursing women are advised not to drink green tea. Caffeine is again one of the substances that should be avoided in pregnancy. Tannins and catechins are other chemicals present in green tea that may be associated with risks in pregnancy. According to BenefitsofGreenTea.info, excessive consumption of green has been linked to a lowered level of folate in pregnant women, which could lead to neural tube defects in babies. Nursing women are advised to avoid drinks with caffeine so that they do not pass caffeine to their babies in their breast milk.

Anemia

• Green tea contains tannins, which in large amounts can block absorption of iron into the bloodstream. This can cause anemia, particularly among some women who are already at risk of lower iron levels.

Dental Discoloration

• Large amounts of tea can cause yellowing of the teeth. Dr Andrew Weil recommends that to lower this risk you should drink good quality green tea because it is less likely to stain teeth. Poor quality tea is "browner" in color when it is brewed.