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Can You Take Vitamin D and Magnesium Together?

Can You Take Vitamin D and Magnesium Together?

In recent weeks we were interested to read about new research published on vitamin D. The Sunshine Vitamin is rarely out of the news, with studies coming to light all the time illuminating benefits for bone health, heart health, even cancer prevention. What pricked our ears this time, though, concerned the link between vitamin D and magnesium. Since we’re often asked by customers ‘Can you take vitamin D and magnesium together?’ (the short answer: yes!), we thought we’d put together a post explaining just what the new study revealed.

Vitamin D and Magnesium: What’s the Link?

It’s well known that certain nutrients have cofactors which they rely upon for proper utilisation and absorption. Take vitamin D and vitamin K as an example: they work together to ensure proper calcium regulation. While vitamin D is responsible for enhancing the absorption of calcium from food, vitamin K controls where that calcium ends up: in bones and teeth rather than in soft tissues (blood vessels, kidneys). Blood vessel calcification can lead to major health problems, which is why ensuring a healthy intake of vitamin K is important if you want to get the most out of your vitamin D.

Sodium and potassium are another dynamic duo, with potassium encouraging the kidneys to excrete sodium and thus promote healthy blood pressure. For this reason, our potassium-to-sodium ratio is considered a valid marker for cardiovascular health.

According to new research, there is a synergistic link between vitamin D and magnesium too. Specifically, those who fail to get enough magnesium may be unable to properly utilise vitamin D. In essence, magnesium deficiency causes vitamin D to be stored and inactive.

The review, which appeared in the Journal of the American Osteopathic Association, went further, pointing out that vitamin D supplements can increase a magnesium-deficient individual’s calcium and phosphate levels.

Furthermore, maintaining healthy magnesium levels means you are likely to require less Vitamin D supplementation to attain sufficient levels. That said, arguments remain over what is ‘sufficient’: the UK Recommended Intake is a mere 400 i.u. while the Vitamin D Council recommend 5,000 i.u. We err on the side of the Vitamin D Council, who have capably outlined their reasoning many times over the years. 400 i.u. per day does not bring us anywhere near the vitamin D levels of our ancestors, or of the hunter-gatherers still living traditional outdoor lifestyles in Africa. That is to say, a blood level of around 40-50 ng/ml.

The researchers involved, from the University of Rwanda College of Medicine & Health Sciences and Harvard University, noted two ways in which intestinal absorption and metabolism of vitamin D was influenced by magnesium. Firstly, they explained that the internal process which converts vitamin D into its biologically active form is magnesium-dependent. Secondly, magnesium acts as a cofactor for the vitamin D-binding protein. And thirdly, all enzymes that metabolise vitamin D appear to require magnesium to facilitate enzymatic reactions in the liver and kidneys.

The study will come as a surprise to many who have supplemented with vitamin D but never paused for a second to consider magnesium.

Perhaps the question shouldn’t be, can you take vitamin D and magnesium together; but should you? The answer – at least according to this new study – is a resounding yes. Proper intake of magnesium will potentiate the effectiveness of vitamin D in your system, thereby helping preserve bones and muscles and fortify the immune system. In turn, activated vitamin D increases your body’s ability to absorb magnesium, which is involved in over 300 biochemical reactions. Thus, a sort of biological feed-forward loop is in effect.

It’s worth noting that vitamin D and magnesium were included in our article 4 Essential Nutrients for Better Overall Health, even before their synergist relationship came to light.

With this in mind, let’s look at a few specific examples of how vitamin D and magnesium could help you regain or maintain good health.

Vitamin D and Magnesium for Depression

Vitamin D and magnesium are often recommended for depression, stemming from a number of studies released over the years. However, one would have to concede that the evidence is rather conflicting. For example, while countless studies have shown a link between vitamin D deficiency and depression, a causal relationship has not yet been established.

What we do know is that vitamin D has some effect, since several receptors in the brain are actually vitamin D receptors. The Vitamin D Council have written commandingly on this topic and recommend somewhere between 5,000 i.u. and 10,000 i.u. for depression. As ever, it is advisable to have your vitamin D levels checked periodically.

What about magnesium for depression? A small human study by the University of Vermont did make headlines last year, finding that “over-the-counter magnesium supplements significantly improved depression in just two weeks”. However, the study was not blind (i.e. people knew what they were taking) so a placebo effect can’t be ruled out.

Since magnesium plays a role in many of the biological processes involved in mood regulation, it is not inconceivable that a beneficial effect would stem from magnesium supplementation. For their part, the researchers opined that “magnesium supplements may be a fast, safe and easily accessible alternative or adjunct to starting or increasing the dose of antidepressant medications.”

Certainly a protocol comprising vitamin D and magnesium would be preferable to pharmaceutical antidepressants for most people, particularly given the unwanted side effects of the latter. If you are experiencing depressive symptoms, resorting to vitamin D and magnesium may be a case of trial and error – but one well worth investigating.

Vitamin D and Magnesium for Weight Loss

Can you use vitamin D and magnesium for weight loss? Again, there are studies which suggest that perhaps you can. One 2013 trial published in the Journal of Nutrition found that a higher magnesium intake correlated with lower levels of fasting glucose and insulin, markers closely related to weight gain. While there are other things to consider – eating a calorie-controlled diet being the main one – magnesium could be a useful adjunct.

As for vitamin D – chiefly responsible for maintaining strong bones and teeth as well as robust immune health – the evidence is compelling. In one 2015 study published in the American Journal of Clinical Nutrition, 218 overweight women were put on a calorie-controlled diet and exercise regimen, with half given a vitamin D supplement and the other half a placebo. When the study concluded, women who had stuck assiduously to their vitamin D supplements lost an average of 7lbs more than their counterparts. The vitamin D group also enjoyed decreased weight circumference and body fat.

Work to establish how exactly vitamin D influences weight loss are ongoing, although it has been suggested that the vitamin reduces the formation of new fat cells and restricts their storage. Regardless, it’s clear that maintaining adequate vitamin D status will only maximise your weight loss endeavours.

Vitamin D and Magnesium for Blood Pressure

We should all take care to maintain healthy blood pressure levels, and both vitamin D and magnesium can help in this regard. As with so many health problems, high blood pressure has been associated with low vitamin D levels – though more work is needed to establish whether vitamin D is the cause or effect. Certainly the study group in this case was large – 155,000 people from Europe and North America – so the link cannot be discounted. For every 10% increase in vitamin D concentrations, individuals enjoyed an 8.1% decrease in hypertension risk.

Meanwhile, a 2016 meta-analysis looking at 34 studies involving over 2,000 patients established that proper magnesium intake may keep blood pressure under control. Taking 300mg of magnesium daily for one month resulted not only in higher levels of magnesium in the blood (as expected) but a reduction in blood pressure. Among patients who took 368mg magnesium daily for two months, a reduction in systolic blood pressure of 2 mm Hg was experienced. Diastolic blood pressure also went down by an average of 1.8 mm Hg.

Again, there are many things you can do to look after your blood pressure without resorting to Vitamin D or magnesium. But do they help? Irrefutably.

Vitamin D and Magnesium for Migraines

At the risk of parroting the aforementioned, numerous studies show that those with chronic headaches are – what else? – vitamin D deficient. Indeed, a Finnish study published last year showed that men with the lowest circulating levels of vitamin D were more than twice as likely to experience headaches at least once per week, compared to those with the highest levels. This aligns with the results of numerous other small-scale studies published over the years.

The same is true for magnesium, in that individuals with migraines often exhibit symptoms of magnesium deficiency. In one oft-cited study, participants who consumed magnesium supplements reduced the frequency of their migraine attacks by 41.6%, compared to just 15.8% in the placebo group. Similar results have been recorded in other double-blind trials.

The take-home? Both vitamin D and magnesium offer hope for migraine sufferers. Yet another reason to avoid deficiency.

How to Increase Vitamin D and Magnesium Levels

There are many benefits to taking vitamin D and magnesium which are not covered in this article. They include for joint pain, sleep, diabetes, even fibromyalgia. The web is a virtual treasure trove of information on these topics, with many articles written by medical doctors and dieticians, so it pays to do your research and make an informed decision.

Given that deficiencies of both vitamin D and magnesium are alarmingly common, it will take a sustained effort for the populace to meet their daily requirements. While magnesium is found in a wide variety of foods including leafy green vegetables, nuts, fish, meat and brown rice, vitamin D is harder to come by. This is why, in the UK, we are advised to use a supplement throughout autumn and winter. In spring and summer, we may get what we need from the sun but even that depends on a host of factors: exactly how much sun you get, your body weight (the heavier you are, the more vitamin D you need), whether you cover up, your skin colour.

As mentioned earlier, the UK Recommended Intake for vitamin D is just 400 i.u. However, in many of the studies quoted in this article a higher ‘therapeutic’ dosage was used. Based on present research, consuming anywhere between 1,000 i.u. and 5,000 i.u. is recommended for most people. The tolerable upper limit advised by the Food and Nutrition Board is 4,000 i.u. per day, though the same board set the No Observed Adverse Effects Level (NOAEL) at 10,000 i.u. per day. The Endocrine Society Practice Guidelines agree that up to 10,000 i.u. per day is “safe for most adults.”

The UK recommended daily intake for magnesium is 300mg for men (19-64 years) and 270mg for women (19-64). However it is higher in the US, where the Food and Nutrition Board (FNB) at the Institute of Medicine of the National Academies set the figure. There, males aged 14 and over are advised to strive for 410-420mg, while females should aim for anywhere between 310 and 360mg.

According to an in-depth report published in 2003, “400 mg/day supplemental magnesium would not be expected to result in any significant adverse effects.” This takes into account even those who eat a magnesium-rich diet, since adverse effects are not associated with magnesium ingested from food. Indeed, the ‘estimated maximum intake’ in this report amounted to 1,400mg per day.

Vitamin D and Magnesium Supplements

So what are the options? Firstly, if you want to avoid vitamin D deficiency, a supplement is almost definitely required unless you live in a warm climate and get plenty of sun on your face throughout the year. Supplements we would recommend include WHC’s Vitamin K2 + D3 and Vibrant Health’s Vitamin D3.

  • Vitamin K2 + D3 provides 90 mcg of vitamin K and 1,000 i.u. of vitamin D
  • Vitamin D3 provides 5,000 i.u. of vitamin D

As discussed earlier, vitamin K is an important cofactor of vitamin D. As such, WHC’s combination supplement is recommended for those who do not consume enough dietary vitamin K. Food sources of vitamin K include leafy greens, broccoli, cabbage, Brussel sprouts and fermented dairy. Incidentally, vitamin K deficiency might be just as harmful as vitamin D deficiency.

Is a magnesium supplement essential? It shouldn’t be, in an ideal world. However, the fact that magnesium deficiency is prevalent in our society indicates that most simply do not eat enough. Furthermore, older adults, people will type 2 diabetes and gastrointestinal diseases, and those with an alcohol dependence have a higher need for magnesium. Elevated stress is another factor which increases one’s magnesium needs.

Although food should always constitute the vast majority of our nutrients, soil depletion due to intensive modern agricultural practice has reduced the magnesium content of crops, meaning less dietary magnesium is available to us than before. This has led Dr. Carolyn Dean, MD – author of The Magnesium Miracle – to claim that "to get enough magnesium today, you need to take supplements."

The magnesium supplement we would recommend is Multimagnesio, a combination of magnesium salts (gluconate, oxide, pyrophosphate, chloride) pressed into a tablet. The absorption of magnesium is closely tied to the type of salt in which it is administered, which is why Italian company Erbenobili have integrated several forms to obtain better absorption. The daily serving is 400mg.

In conclusion, vitamin D and magnesium can – and should – be taken together. Ensuring a suitable daily intake of both key nutrients is key to achieving higher levels of wellbeing, and there are specific conditions for which supplemental intake is particularly recommended.


Multimagnesio consists of five different magnesium salts to increase bioavailability and efficacy. The absorption of magnesium, as well as for other minerals, is closely linked to the type of salt it is administered in. Multimagnesio's constituents are activated using the spagyric method by the renowned Italian company Erbenobili, and a daily serving will meet 100% of your magnesium needs.

WHC Vitamin K2 + D3

Formulated by award-winning fish oil manufacturer WHC, Vitamin K2 + D3 is a high-quality dietary supplement. Engineered to support bone, muscle and immune health, it combines the superior forms of vitamin D and vitamin K in a single pearl tablet. If you're worried about getting enough of these important nutrients, just take one tablet per day to ease your mind and support good health.