Magnesium Deficiency Is Often Overlooked, But There Are Ways to Fix It

If you’re looking to get more vitamin D in your diet, take it with a side of magnesium.
That mineral appears to help regulate levels of vitamin D, which in turn manages the levels of other minerals such as calcium and phosphorus. It also improves bone strength and possibly reduces the risk of cardiovascular disease and cancer.
Researchers at the Vanderbilt-Ingram Cancer Center in Tennessee say that magnesium raises levels of vitamin D in people who need more of that substance and lowers levels among those who have an excess amount of the vitamin in their system.
The researchers reached their conclusions after conducting a randomized clinical trial involving 250 people considered at risk of colorectal cancer.
The study, published in the December 2018 issue of the American Journal of Clinical Nutrition, was the first direct evidence that magnesium plays a role in vitamin D regulation.
A previous study from the same group of researchers found an association between low magnesium levels and low vitamin D levels.
Researchers also have noted variations in vitamin D synthesis, with some people failing to raise their levels of the vitamin even when taking high-dose supplements.
Dr. Qi Dai, the lead author on the latest study and a professor of medicine at Vanderbilt University Medical Center, said their research explains why.
“Magnesium deficiency shuts down the vitamin D synthesis and metabolism pathway,” Dai said.
Vitamin D, magnesium deficiencies
Exposure to sunlight is the primary way to get vitamin D.
However, deficiency of the vitamin is common, especially in the northern United States and Canada.
About 40 percent of people in the United States and half of people worldwide may be deficient in vitamin D.
Foods rich in vitamin D include salmon and other fatty fish, egg yolks, mushrooms, and milk and juice fortified with the vitamin.
“Vitamin D insufficiency is something that has been recognized as a potential health problem on a fairly large scale in the U.S.,” said Martha Shrubsole, PhD, a study co-author and a research professor of medicine at Vanderbilt University Medical Center. “A lot of people have received recommendations from their healthcare providers to take vitamin D supplements to increase their levels based upon their blood tests.”
“In addition to vitamin D, however, magnesium deficiency is an under-recognized issue,” she told Healthline. “Up to 80 percent of people do not consume enough magnesium in a day to meet the recommended dietary allowance.”
“We know magnesium plays many vital roles in the body and is a mineral that is essential to many many cellular functions. It has a clear role in helping with heart health, blood pressure, migraine treatment, and more,” said Dr. Arielle Levitan, co-founder of Vous Vitamin and co-author of “The Vitamin Solution: Two Doctors Clear the Confusion About Vitamins and Your Health.” “It is not surprising that one of its many functions is to facilitate vitamin D’s activities.”
“This has big implications for bone health, suggesting that taking a magnesium supplement may help people get to a desired level of vitamin D faster,” Levitan told Healthline. “Magnesium may also facilitate the actions of vitamin D on bone health, though the data to prove an actual benefit in regards to fractures is not clearly established.”
Dai said further research is needed to determine the molecular mechanism underlying magnesium’s effect on vitamin D synthesis.