I'm not convinced that a hair test is a reliable indicator of magnesium deficiency. Magnesium is a very stable molecule, and any quality diet would have an abundance of magnesium, since it is in anything green. Your body seems to be telling you something and it might be a good idea to listen. Magnesium is the enemy of nitrogen and an excess of magnesium can cause protein depletion and nitrogen deficiency. Nitrogen is required for potassium to enter cells, so excess magnesium can also cause a potassium deficiency even if you have enough blood potassium. Calcium deficiency is far far more common. And more important. Calcium is required by weight and volume more than any other mineral and it is easy enough to test for. Since calcium acts as our pH buffer, you can test your urine pH to get an idea of your calcium status. Since calcium is needed for neurotransmitter release, a deficiency can affect anything from muscle movement and cramps to mood and behavior.