Magnesium's Role in Calcium Absorption & Bone Health

Calcium makes up 50 percent of all hard minerals in the body, with magnesium in muscles, the brain and nerves. Magnesium plays an important role in calcium absorption.

Function

• Calcium is only absorbed in the acidic duodenum, not in the alkaline lower intestines. Calcium deposits in joints are the result of insufficient acid, which may be caused by excessive use of antacids.

Effects

• Two-thirds of all kidney stones in the U.S. are believed to be calcium stones caused by too high a ratio of calcium to magnesium.

Expert Insight

• According to Joseph Marion, author of "Anti-Aging Manual: The Encyclopedia of Natural Health," 50 percent to 60 percent of the calcium in cow's milk is not digestible, but contributes to artery blockage, arthritis, kidney and gall stones, and blocked prostate.

Factors

• The ideal calcium-to-magnesium ratio is 2:1, according to Phyllis Balch, author of "Prescription for Nutritional Healing." Both iron and excess intake of zinc and phosphorus are known to interfere with calcium absorption, while magnesium is essential for calcium absorption.

Considerations

• Kelp, marine phytoplankton, green leafy vegetables and brewer's yeast are rich food sources of calcium and magnesium.