Can’t figure out why you’re always dragging? Lack of iron may be to blame – even if you’re not anemic. When fatigued women with normal blood levels took iron supplements for 12 weeks, they reported feeling 50 percent less tired, according to a new study published in the Canadian Medical Association Journal. It’s possible that they had enough of the mineral in their bloodstream but inadequate amounts stored in their brain, muscles, and other tissues, probably because of blood loss during menstruation, says lead study author Paul Vaucher, a Ph.D. student at the University of Geneva in Switzerland. Participants took 80 milligrams each day, which is much more than the recommended daily value of the 18 mg contained in many multivitamins. However, don’t self-treat with larger doses without talking to your doctor first, as too much iron can be dangerous. And keep in mind that a pill isn’t the only answer: Beef, seafood, and poultry are also great sources of iron.