During pregnancy, a woman's iron requirement doubles to 30 mg but reverts to 15 while she's breastfeeding. After menopause, women need only 10 mg a day. Meat is the richest source, and the darker the meat, the more iron it contains. Also check labels for iron-fortified cereals. It's a tricky question.
Some people can definitely benefit from supplements.
On the other hand, an estimated 10 percent of Americans carry a gene that causes them to absorb 50 percent more iron than normal. Taking iron supplements can push their bodies into full-blown iron overload, which can lead to heart and liver damage in extreme cases. A standard blood test will not reveal this condition and you can have it even if you're iron deficient. Most people's bodies are good at regulating the amount of iron they absorb from food. But getting more than the recommended amount can cause heart and liver problems if you're susceptible to iron overload.