Side Effects of Iron Supplements and Dong Quai

Are there any negative side effects from taking iron supplements and dong quai?

Iron supplements can have negative health effects unless you know that you are iron deficient. Iron facilitates free radical damage and increases risk of heart attack.
Coffee, tea, red wine, bran and beans block iron absorption. If you are iron deficient, avoid taking these within 3 hours of taking the iron supplement or iron-containing foods like meat, almonds, figs, spinach and watercress.
Dong quai is contraindicated in pregnancy due to its hormonal effects. It encourages bleeding, so should not be used during menstruation.