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Time to ditch the 2:1 calcium-magnesium ratio


After a recent talk at Expo West with Carolyn Dean, MD, ND, magnesium expert and medical director of the nonprofit Nutritional Magnesium Association, I had the urge to call my mom, my sister, and my women friends to ask them to take a good look at their calcium supplements, and most likely, to consider changes to their regimen.

I’ve been hearing that typical bone health supplements contain too much calcium, especially in relation to cofactors like magnesium and vitamin D that help the body effectively absorb and use calcium. My ears have been especially pricked since 2010, when a review of Women’s Health Initiative (WHI) data suggested that taking calcium supplements may raise heart disease risk in post-menopausal women.

As I was writing up notes today on the points Dean had highlighted about magnesium in relation to calcium, I saw online that she had just done a thorough write-up herself, as you can read in the release below:

"About 43 percent of the U.S. population (almost 70 percent of older women) use dietary supplements containing calcium(1), but without balancing their calcium with magnesium, they may be at risk, says Carolyn Dean, MD, ND. Most people, including the majority of MDs, do not understand key facts about calcium and its sister mineral, magnesium:

  • Typically, less than half of calcium intake is absorbed in the gut(2), the rest either being excreted or potentially forming kidney stones or being transported to soft tissues where it can harden (calcify).
  • Adequate levels of magnesium are essential for the absorption and metabolism of calcium and vitamin D.

Magnesium converts vitamin D into its active form so that it can aid calcium absorption. Magnesium also stimulates the hormone calcitonin, which helps to preserve bone structure and draws calcium out of the blood and soft tissues back into the bones, lowering the likelihood of osteoporosis, some forms of arthritis, heart attack and kidney stones.

  • There is a growing amount of scientific evidence pointing to high calcium - low magnesium intake leading to calcification, or hardening, of arteries (atherosclerosis—the number one cause of death in the U.S.), osteoporosis and osteoporotic bone fractures(3, 4).
  • Recommendations for calcium intake vary greatly. In the U.S., adults are told to take 1,000 mg per day and women over 50 are told to take up to 1,500 mg. In the United Kingdom, the RDA is 700 mg daily, while the World Health Organization recommends only 400-500 mg.

Often supplementation is taken without consideration for the amount of calcium in the diet both from food sources and water. Many people, especially those consuming dairy products, have high-calcium diets. This can lead to a greater amount of unabsorbed calcium.

"Most people—and most MDs—do not understand the importance of calcium-magnesium balance at a cellular level. The effectiveness and benefits of calcium with respect to bone health and the prevention of osteoporosis are enormously impaired in the absence of adequate levels of magnesium in the body," Dr. Dean states.

"If we consume too much calcium without sufficient magnesium," according to Dean, "not only will we create stress within the body but the excess calcium won't be utilized correctly and may become toxic. Magnesium keeps calcium dissolved in the blood. Too much calcium and too little magnesium can cause some forms of arthritis, kidney stones, osteoporosis and calcification of the arteries, leading to heart attack and cardiovascular disease(5).

"The commonly agreed-upon ratio of 2:1 calcium to magnesium found in many supplements traces back to French scientist Jean Durlach(6)," explains Dean, "who stipulated the 2:1 ratio as an outermost not-to-be-exceeded level when considering calcium intake from all sources (food, water and supplements). This has been largely misunderstood and is taken as a recommendation of a 2:1 calcium-to-magnesium imbalance.

"The fact that most people do not get their minimum daily requirement of magnesium exacerbates the situation. The high calcium - low magnesium diet of most Americans, when coupled with calcium supplementation, can give a Ca to Mg imbalance of 4: or 5:1, which constitutes a walking time bomb of impaired bone health and heart disease."

Dr. Dean recommends monitoring calcium intake, supplementing with vitamin D, getting the minimum daily requirement of magnesium, "and going for a 1:2 or at the very least a 1:1 calcium-magnesium balance."

A 32-page guide to the benefits of magnesium and how to avoid osteoporosis, strengthen bones naturally and support a healthy heart is available as a free download."

In my role as a health and science editor, I know that beyond its role with calcium, magnesium helps with myriad other body functions, including: heart health, migraines, pain, anxiety, constipation, diabetes and more. I have started taking magnesium at night myself and find it helpful in several ways. Eating magnesium-rich foods can also help: kelp, wheat bran and germ, almonds, cashews, molasses, brewer’s yeast.

Do you take calcium and/or magnesium supplements? What’s your take on the best way to supplement these minerals?

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