Good Bones

In praise of magnesium’s pivotal role in helping prevent osteoporosis.
Magnesium is plentiful in green vegetables, nuts and seeds, beans and whole grains.   Photo: @alison_wu

By Tapp Francke Ingolia

What treatment comes to mind when the issue is strengthening bones? Calcium. With what image? Pictures of movie stars with milk mustaches under the slogan “Got Milk?” The implication is that the daily intake of calcium-rich milk will keep bones strong and ward off encroaching osteoporosis. But that’s only part of the solution. What we don’t hear about is one of calcium’s co-pilots, magnesium. Why not a “Got Magnesium?” ad campaign—touting the benefits of magnesium-rich foods such as dark chocolate and avocado—along with “Got Milk?” Both calcium and magnesium are essential to helping maintain healthy bone density.

Sadly, many people have a diet that is deficient in magnesium, though it is abundant in a wide array of green, leafy vegetables, nuts and seeds, beans and whole grains. Why the deficiency? Because many people have diets high in processed foods, with the majority of the magnesium stripped away. They are missing this magnificent cofactor in over 300 enzyme systems that regulate biochemical reactions in the body, especially the bones. Between 50 and 60 percent of it shows up in the bones, the rest in soft tissues. That leaves many with substandard serum magnesium, and more at risk of developing osteoporosis.

How does magnesium work? Despite its secondary position to calcium, magnesium influences the activity of osteoclasts and osteoblasts in cells responsible for resorbing and growing new bone. Our bones are in a constant state of breaking down and building up, a process called bone remodeling; magnesium plays an important role in making sure this happens successfully. Magnesium also helps maintain levels of parathyroid hormone in the body, as well as the active form of vitamin D, both of which are the major regulators of bone homeostasis. Additionally, magnesium stimulates the thyroid hormone calcitonin, which helps to deliver calcium from the tissues and bloodstream back into the bones. Adequate magnesium levels in the body can lower the risk of developing osteoporosis.

Osteoporosis is a complex disorder with many possible causes. Typically experienced later in life, it is characterized by loss of bone mass, leaving bones weaker and more brittle. Individuals become more vulnerable to fractures of the hip and spine. Postmenopausal women are the most susceptible to this condition, for a couple of reasons. One is that women tend to have smaller body frames and therefore less bone mass than men. The second has to do with women’s natural decline in bone-protective estrogen in menopause.

The 2:1 ratio between calcium and magnesium appears to be critical in healthy bone maintenance. When supplementing magnesium, a dose of 300 mg to 350 mg of the highly absorbable chelated or glycinate form is recommended (so, take 350 mg of magnesium to 700 mg of calcium). Of course, a diet rich in natural magnesium sources like spinach, almonds and brown rice will also help maintain healthy magnesium levels. So when considering strong bones, make sure to take your calcium, but don’t forget its essential cohort—the mighty magnesium. Your bones will thank you. Tapp Francke Ingolia is a contributing health editor to Purist and the founder of