The U.S. Preventive Services Task Force, a government-appointed panel of experts, issued a report stating that taking vitamin D and calcium supplements may not help prevent bone fractures in postmenopausal women, while also increasing the risk of kidney stones.

“This is not surprising,” says Carolyn Dean, MD, ND, magnesium expert and Medical Advisory Board member of the nonprofit Nutritional Magnesium Association, “because adequate levels of magnesium in the body are essential for the absorption and metabolism of vitamin D and calcium. Magnesium converts vitamin D into its active form so that it can help calcium absorption and help prevent clogged arteries by drawing calcium out of the blood and soft tissues back into the bones where it is needed to build healthy bone structure.”

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Nutrients act in a synergetic way in the body. Absorption and metabolism of a particular nutrient will be affected, to a greater or lesser degree, by the other nutrients available to the body. This is also true with vitamin D.

According to the nonprofit Vitamin D Council, “In order to receive the most health benefit from increased levels of vitamin D, the proper cofactors must be present in the body. Vitamin D has many cofactors, but the ones listed here are the most important, with magnesium topping the list: Magnesium, Vitamin K, Vitamin A, Zinc and Boron.”

According to research studies, magnesium has been found to influence the body’s utilization of vitamin D in the following ways: Magnesium activates cellular enzymatic activity. In fact, all the enzymes that metabolize vitamin D require it. Low magnesium has been shown to alter, by way of decreasing, production of vitamin D’s active form, 1,25(OH)2D (calcitriol). Magnesium is needed to exert positive influence over the human genome and may be involved in the genetic actions of vitamin D. Magnesium possibly has a role in vitamin D’s effect on the immune system.

Animal studies have shown magnesium is also necessary for vitamin D’s beneficial actions on bone. Dr. Dean concurs: “It is vitally important that studies on the efficacy of vitamin D and calcium in relation to bone health are not done in isolation in the absence of magnesium. The fact that magnesium works synergistically with vitamin D and calcium by stimulating the specific hormone calcitonin—which helps to preserve bone structure and draws calcium out of the blood and soft tissues back into the bones, preventing osteoporosis, some forms of arthritis and kidney stones—cannot be overlooked.” Dr. Dean concludes, “The many studies pointing to the importance of these two nutrients to the prevention of both heart disease and osteoporosis, and the fact that magnesium can be found to increase the effectiveness of vitamin D and calcium, make finding out about this vital mineral that much more important.” 

A 32-page guide to the benefits of magnesium, along with magnesium deficiency symptoms, written by Dr. Dean, is available as a free download at www.nutritionalmagnesium.org.