What You Need to Know: Unlike other nutrients, excess iron cannot be excreted by the human body, causing it to build up in the brain and other tissues and organs impacting the liver. Premenopausal women, especially those with heavy periods, may benefit from iron supplementation, but it's not usually necessary after menopause.
Who Should Take It: Vegans, anemic women and people with gastrointestinal problems.
What to Watch Out For: Constipation. Iron can also decrease the absorption of some antibiotics and drugs prescribed for thyroid problems and can contribute to osteoporosis.
Get It Naturally: Fish, poultry and red meat are good sources.