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Vitamin D’s ability to prevent cancer and other diseases depends on magnesium

Vitamin D’s ability to prevent cancer and other diseases depends on magnesiumEpidemiological studies have led to different results when it comes to vitamin D and its ability to protect against cancer, infections, and various diseases. However, according to a new study published in Cancer Research, this is because magnesium is involved in the activation of vitamin D, on which all cells depend. It therefore does no good to take supplements of vitamin D, if you lack magnesium. And this is exactly the case with many people who eat unhealthy diets, are stressed, use medicine etc.

Vitamin D is important for our bones and immune defense. Recent studies also show that it is important for preventing inflammation, depression, and cancer. Science has even found that vitamin D and magnesium work closely together like a team. For that reason, it is vital to get enough vitamin D and to make sure to have the right balance between the two nutrients in order to enable proper functioning of many physiological functions and for good health in general.
It is widely accepted that vitamin D supplements increase the uptake of calcium. Then again, if you lack magnesium, it increases your risk of osteoporosis, because one of magnesium’s roles is to make sure to embed calcium in our bone cells. In a study of patients with Rickets, which is the condition caused by severe vitamin D deficiency, injections of vitamin D in large quantities (1,500 micrograms) did not correct the actual deficiency. However, when magnesium was also administered, the bone cells were suddenly able to absorb the calcium they needed, and then the treatment against Rickets worked as expected. That way, one can use magnesium supplements to help unsuccessful vitamin D therapy work properly. The same is the case with vitamin D used to prevent cancer and a number of other diseases.

There are several kinds of vitamin D, and the most important forms are:

Vitamin D2 (ergocalciferol). Found naturally in the plant kingdom.

Vitamin D3 (cholecalciferol). Found naturally in the animal kingdom, can be converted into the active forms.

How magnesium activates vitamin D

The form of vitamin D called cholecalciferol is initially synthesized in our skin by means of sunlight a form of cholesterol. This is the same form of vitamin D as we get from vitamin D supplements.
Helped by magnesium-containing enzymes, the liver then converts cholecalciferol to 25-hydroxycholecalciferol D3 - or 25(OH)D3 – which is the form of vitamin D that is measured in blood tests. When we need vitamin D, 25(OH)D3 is converted in the kidneys into the active form of vitamin D called 1,25-dihydroxycholecalciferol D3. This conversion requires the presence of other magnesium-containing enzymes. Lack of magnesium can therefore result in a host of different diseases caused by a deficiency of activated vitamin D.

Vitamin D and magnesium are both vital for preventing cancer

Earlier studies (in vivo and in vitro) have shown that the activation of vitamin D depends on magnesium. Now, a team of scientists has conducted a double-blind, randomized, placebo-controlled study of the interaction between magnesium and vitamin D, where they also looked at whether or not magnesium increases blood levels of activated vitamin D. In their study that involves the prevention of colorectal cancer, 250 participants were randomly assigned to supplements of magnesium or matching placebo. The researchers found that magnesium supplements affected blood levels of 25(OH)D3 and certain other forms of vitamin D. They also observed that there was a difference between supplementing with vitamin D alone and taking supplements of vitamin D together with magnesium.
According to the scientists, their new study may explain why earlier studies of vitamin D’s ability to prevent cancer have had different outcome. The new study is published in Cancer Research.

The widespread lack of vitamin D and magnesium is a dangerous cocktail

Our main source of vitamin D is sunshine during the summer. We only get small amounts of the nutrient from the food we eat. Therefore, vitamin D deficiencies are rather common in the northern hemisphere, where there is hardly any sun in the winter period. An estimated 50 percent or so of Americans lack magnesium, and a similar figure may apply to Europeans. In other words, there is a widespread lack of both nutrients, and that may affect our health in various ways, not just short term but also in the long run.

Overview of interactions between vitamin D and magnesium
Presence of vitamin D Vitamin D type and enzyme activity
Food and supplements Cholecalciferol
Skin Cholecalciferol
Synthesized from cholesterol and UVB-rays from the sun
Liver 25-hydrocholecalciferol D3/ 25(OH)D3
Produced with help from the enzyme 25-hydroxylase that requires magnesium
Kidneys 1,25-dihydroxycholecalciferol D3
Produced with help from the enzyme 1-alfa-hydroxylase that requires magnesium

Why so many people lack magnesium

The best sources of magnesium are kernels, almonds, nuts, whole grain, cabbage, beans, and other compact vegetables.
Over the last decades, magnesium deficiencies have become increasingly common due to modern farming methods, unhealthy diets and too many refined foods. A large intake of alcohol and other stimulants, birth control pills, diuretics, beta blockers, antacids, corticosteroids, insulin resistance, excessive training, and stress also inhibits the uptake of magnesium and deplete the body’s levels of the important mineral
Our actual need for magnesium may therefore be far greater than the reference intake level.

Measuring the body’s magnesium levels often gives misleading results

It is difficult to determine the body’s magnesium status, as only 1% of the body’s magnesium reserves are found in the blood. The best way to determine a person’s magnesium status is a whole blood analysis that also measures the amount of magnesium inside the blood cells, not just the plasma.


Qi Dai el al. Abstract CT093: Bimodal relationship between magnesium supplementation and vitamin D status and metabolism: Results from randomized trial. Cancer Research July 2018

Anne Marie Uwitonze, Mohammed S Razzaque. Role of magnesium in Vitamin D Activation and Function. The Journal of the American Osteopathic Association. 2018

American Osteopathic Association. Low magnesium levels make D-vitamin ineffective. ScienceDaily. 2018

Keep magnesium levels topped to benefit from vitamin D, research suggest. Nutrition Insight

Andrea Rosanoff et al. Essential Nutrient Interactions: Does Low or Suboptimal Magnesium Interact with Vitamin D and/or Calcium status. Advances in Nutrition 2016

Mark J Bolland et al. Vascular events in healthy older women receiving calcium supplementation: randomised controlled trial. BMJ 2008

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