Science - can a strong magnet have an effect on a heart?

magnetic fields are not felt by human beings, but their effects can be dramatic on human beings. Magnetic fields have been known to effect human cells and hearts but not much research has been done on it, because it could effect many industries. Just remember that humans today are bombarded with so much magnetic fields, and radio waves, and other cellular waves that nothing can be done, because no one can stop technological advancements and that is the price we have to pay, remember nothing is really free.