Terranova Calcium Magnesium 2:1 Complex provides essential minerals calcium and magnesium in the perfect ratio for absorption, along with Magnifood Botanicals for greater bioavailability. It is important to maintain a healthy balance of both calcium and magnesium to support bone health, circulation and immune function. A ratio of 2:1 is the naturally occurring ratio found in the blood; this supplement is in a ratio that nature intended. Calcium and Magnesium take on opposite roles in the body – calcium is a muscle stimulant, whilst magnesium is a muscle relaxant, so it is vitally important that these nutrients are balanced appropriately. Both minerals in this formula are in highly absorbable forms – calcium as carbonate and citrate, and magnesium as oxide and citrate. Calcium Magnesium Complex contains 500mg calcium and 250mg magnesium.