Answer to Question 1
Magnesium helps stabilize high-energy compounds in the body, is vital for energy metabolism, is needed for over 300 chemical reactions, and influences nerve and muscle function, especially the heart tissue. Given the heart tissue's reaction to a lack of magnesium, there is great interest in whether a mild magnesium deficiency may increase the risk for cardiovascular disease. Additional research has looked at whether a magnesium deficiency may predispose people to type 2 diabetes and even migraine headaches. No controlled clinical studies have been conducted, and thus no convincing evidence exists.
Answer to Question 2
Like calcium concentrations, the concentration of blood phosphorus is regulated by calcitriol (vitamin D), PTH, and calcitonin. When blood phosphorus declines, calcitriol and PTH are released, and result in increased phosphorus absorption in the small intestine and phosphorus resorption from bones. When blood phosphorus is elevated, cacitonin will stimulate the bone-building activity of osteoblasts, which will take up phosphorus from blood; blood phosphorus levels will then return to normal.