The Vitamin D-Magnesium Connection: Are You Getting Enough of Both?

July 14, 2024

by Cathe Friedrich

Vitamin D gets more than its share of attention these days. We hear about how important it is for healthy bones. Beyond that, it helps support a healthy immune system. But recently, we’re hearing more about the role magnesium plays in ensuring you get the full benefits of vitamin D, the sunshine vitamin.

What scientists are discovering is that you need magnesium to activate and regulate vitamin D in your body. So, they’re a match made in heaven, and you don’t want to be deficient in either vitamin D or its sidekick magnesium.

Why Vitamin D and Magnesium are the Ultimate Power Couple

Without enough magnesium to activate vitamin D it can’t work its full magic for bone and immune health. The vitamin D you get from food, sunlight, or supplements, could remain inactive and offer little or no benefit.

Research finds that even people who take vitamin D supplements and spend hours in the sun each week may not get vitamin D’s benefits if they don’t consume enough magnesium. If their cellular magnesium supply is low, they may not be able to activate it and enjoy its full benefits.

The Magnesium Deficiency Epidemic: Are You at Risk?

How common is magnesium shortfall? Depending on the source you look at and the type of testing, magnesium deficiency ranges from 30% to 80% of the population. Around half of Americans don’t consume enough magnesium. This should be a wake-up call because you need magnesium for more than 300 chemical reactions that affect the health of your heart, muscles, bones, and nervous system. You even need magnesium for energy production, as your cells struggle to make ATP, a cell’s energy currency. Talk about feeling tired!

Why is magnesium deficiency so common:

Processed foods: The Western diet is rich in refined grains, added sugars, and processed foods that are often low in magnesium. This is 60% of what people eat.
Poor soil quality: Modern farming practices are so intensive that they deplete the soil of magnesium, giving less for crops to take up.
Medications: Many people take medications that reduce magnesium levels by reducing how much is absorbed or by causing more to be excreted. Examples are diuretics and proton pump inhibitors.
Stress: Chronic stress can deplete magnesium levels in the body.

The Synergy of Magnesium and Vitamin D

Not only does magnesium activate vitamin D, but magnesium itself is also a “must-have” mineral for bone health. So, step aside, calcium, and give magnesium the spotlight! When you have enough of both, you’re better able to build and maintain bone mass.

Vitamin D helps you absorb calcium from your gut, but you need magnesium to integrate calcium into your bones. So, you need adequate quantities of both to lower your risk of osteoporosis. Recent research also shows you need vitamin K2 to direct calcium to your bone and keep it from attaching to your arteries, where it would be harmful. So, for best bone health, you need a trio of nutrients– vitamin D, magnesium, and vitamin K2.

How to Boost Your Vitamin D Level

How much of these key nutrients do you need? First, let’s look at vitamin D. The recommended daily intake (RDA) for vitamin D is 600 IU for adults under 70 and rises to 800 IU daily after 70. However, this won’t be sufficient if you already have a low level and need to raise it. In fact, some experts now believe that people need more than 1,000 IU of vitamin D daily and up to 4,000 IU daily if they’re prone to deficiency.

To get vitamin D, you’ll need to spend 10-30 minutes in direct sunlight several times per week. The amount varies depending on the time of day, the latitude, and your skin tone. Sunlight stimulates your body to produce vitamin D naturally.

Unfortunately, most people can’t get enough vitamin D from food alone. Foods that contain modest amounts of vitamin D include fatty fish, like salmon, fortified foods (like cereals, yogurt, and orange juice), egg yolks, and mushrooms exposed to ultraviolet light. Because whole foods contain little natural vitamin D, most people need adequate sunlight or supplements to avoid a deficiency.

If you take a vitamin D supplement, work with a doctor who can monitor your levels and avoid taking over 4000 IU per day without close monitoring, as toxicity is a risk if you take large quantities. By checking your vitamin D level regularly, you’ll know if you need to modify your sun exposure and supplement regimen. Doing so is also important for avoiding toxicity.

Optimizing Your Magnesium Intake

How about magnesium? The RDA for magnesium is 400-420 mg for adult men and 310-320 mg for adult women. To boost your magnesium intake, focus on eating more whole foods – whole grains, seeds, nuts, beans, lentils, avocados, and fatty fish, like salmon. Replacing ultra-processed foods that are often low in magnesium with these whole food sources can help you get on track.

Checking your magnesium level is trickier compared to vitamin D. Standard blood tests that measure magnesium only measure the amount of magnesium in the serum or your blood. It doesn’t tell you if you have enough magnesium inside your cells, which is important for health.

The best test for this is a magnesium RBC (red blood cell) test. It measures the amount of magnesium inside your blood cells, a better indicator of how much bioavailable magnesium your cells have access to, as 99% of magnesium inside your body is inside your cells. Make sure you’re managing stress too, as chronic stress makes it harder to maintain a healthy magnesium level.

Conclusion

So, now you know why magnesium and vitamin D are close pals. These two nutrients share a bond of synergy and cooperation. When you have enough of both, you enjoy the full benefits that each offer. Without enough magnesium, you don’t tap into the full benefits of vitamin D. So, the next time you reach for your vitamin D supplement, think about whether you’re getting enough of its trusty sidekick, magnesium. Otherwise, you’re selling yourself short!

References:

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Srivastava SB. Vitamin D: Do We Need More Than Sunshine? Am J Lifestyle Med. 2021 Apr 3;15(4):397-401. doi: 10.1177/15598276211005689. PMID: 34366736; PMCID: PMC8299926.
“Vitamin D – Health Professional Fact Sheet – Office of Dietary ….” https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/.
“Magnesium – Health Professional Fact Sheet – Office of Dietary ….” https://ods.od.nih.gov/factsheets/magnesium-healthprofessional/.
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DiNicolantonio, James J, James H O’Keefe, and William Wilson. “Subclinical Magnesium Deficiency: A Principal Driver of Cardiovascular Disease and a Public Health Crisis.” Open Heart 5, no. 1 (January 1, 2018): e000668–68. https://doi.org/10.1136/openhrt-2017-000668.
“Micronutrient Inadequacies in the US Population: An Overview.” Linus Pauling Institute, April 20, 2018. https://lpi.oregonstate.edu/mic/micronutrient-inadequacies/overview.