Why You May Want To Take Your Magnesium And Vitamin D Together

Is there really such a thing as the best time to take your vitamins every day? According to family medicine physician Dr. Rodolfo Perez-Gallardo, timing can make a big difference in terms of vitamin and mineral supplementation. As he explained to Cleveland Clinic, "When people don't take vitamins the proper way, they don't see improvement." 

For that reason, he recommends taking vitamin D (and other fat-soluble vitamins) after fattier meals to encourage more absorption. According to a 2010 study in the Journal of Bone and Mineral Research, after three months of taking vitamin D after their most substantial meal of the day, 17 vitamin D-deficient individuals saw a roughly 50% improvement in their vitamin D levels. 

But while you're updating your vitamin D dosage schedule, you might want to consider taking it alongside your magnesium supplement. The body doesn't easily absorb magnesium; on average, only 30% to 40% of magnesium is absorbed by the body (via National Institutes of Health). However, partnering magnesium with vitamin D can improve the bioavailability for both nutrients.

When vitamin D is present, the stomach is capable of absorbing larger quantities of magnesium. Vitamin D and magnesium don't compete for absorption, either, meaning that one doesn't get a bigger boost at the expense of the other. (Here's the connection between magnesium and vitamin D, explained.)

Additionally, a 2013 review from BMC Medicine revealed that when your body has enough magnesium, you're less at risk of becoming deficient in vitamin D. In fact, a 2019 review in the American Journal of Therapeutics concluded that magnesium is "essential" when it comes to metabolizing vitamin D.

As academic researcher Dr. Mohammed S. Razzaque, who studied vitamin D and magnesium, explained to Doctors of Osteopathic Medicine, "People are taking vitamin D supplements but don't realize how it gets metabolized. Without magnesium, vitamin D is not really useful or safe."

In addition to helping your body absorb a higher percentage of both nutrients, you may find that magnesium and vitamin D can help you meet some health-related goals. For instance, they can work toward improving your bone health. According to Dr. Mohammed S. Razzaque (via Doctors of Osteopathic Medicine), getting enough magnesium and vitamin D can help reduce a person's risk of osteoporosis and bone fractures, respectively. (You can also improve your bone health by knowing which foods to eat and which to avoid.)

Magnesium and vitamin D might help you mentally as well. Speaking with the Cleveland Clinic, psychiatrist Dr. Joseph Austerman endorsed the potential use of magnesium to help calm misfiring neurotransmitters to minimize anxiousness. "In some ways, magnesium can mimic what some of our anxiety medications do," said Dr. Austerman. Low amounts of vitamin D have been connected to anxiety, so getting adequate vitamin D and adding magnesium to your diet could reduce episodes of anxious feelings and depression.