Some folks say that magnets can heal sore muscles and bones, so they strap "therapeutic magnets" around their wrists or backs or whatever is ailing them. The claim is that the magnets are manipulating the blood flow in the body because of its iron content. There are two things wrong with this claim, though. First, those magnets are too weak to penetrate their casing and then our skin. And even if they could, the iron in our blood is not attracted to magnets. If it were, anyone who ever had an MRI scan (generating a 15,000 Gauss field) would blow up! If an MRI doesn't affect the blood, there's no way a 100 Gauss therapeutic magnet can.