Question: Does the Earth’s magnetic field affect human health?

Answer:
Not directly, no. High-altitude pilots can experience enhanced levels of radiation during magnetic storms, but the hazard is due to the radiation, not the magnetic field itself. Direct effects on human health of the magnetic field at the Earth’s surface are, quite frankly, insignificant. The primary effects of geomagnetism are on the health of electrically-based technological systems that are critically important to the modern civilization of humanity, not the humans themselves.