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Their Vitamin D Won’t Come Up?!

Here at SAFM, we frequently affirm that the old adage “you are what you eat” is far from accurate.  Actually, our nutrition is what we eat, digest, absorb, convert to final forms, and get past the cell membrane (and where relevant, into a sensitive receptor!).  Nutrients don’t act independently. 

This week’s clinical tip is an oldie-but-a-goodie reminder of this truth.  If one is truly Vitamin D deficient, it’s not enough to just “take a supplement” or “get more sunshine”

Do you know why?  

First of all, we have to be able to digest and absorb Vitamin D from an oral supplement.  This requires, in particular, sufficient digestive enzyme and bile function.  Individuals who have Type 2 diabetes are likely (30%+) to have exocrine pancreatic insufficiency that impairs dietary fats and fat-soluble vitamin absorption.  Individuals with hepatic-biliary congestion or who no longer have a gallbladder may struggle as well.  Take care to ensure sufficiency of fat-soluble vitamins and minerals in particular for individuals with ongoing gut dysbiosis or pathogenic overgrowth which can also contribute to intestinal malabsorption of nutrients.

But these points of interconnectedness may have already been clear to you.  The more important reminder here is to assess and ensure magnesium sufficiency before starting a Vitamin D boost (from sunshine or supplement)The body needs magnesium to convert Vitamin D to its final usable form.  If high Vitamin D intake/synthesis puts a magnesium demand on a body that is already deficient (or borderline deficient) in magnesium (common in our practices!), then a patient may experience debilitating symptoms once adding in more sunshine or a Vitamin D supplement.  That is, a Vitamin D boost triggering symptoms of magnesium deficiency.  Yes!  Especially if you jump right in with a high dose (typical Rx?).   Optimal magnesium status is necessary for optimal Vitamin D status.  Many practitioners have been surprised by this dynamic.  Now you can proactively prevent it! 

If a client starts using or increases dosage of D3 and has surprising symptoms appear (e.g. headache, muscle cramp/spasm, acid reflux, anxiety, trouble sleeping), they may blame the Vitamin D. However, these are symptoms of insufficient magnesium.   It is most likely because their magnesium levels have been driven too low (due to usage in the vitamin D conversion). Remember that magnesium is a top American nutrient deficiency (and has been for many years). Many of your patients may need a supplement to get to optimal (vs. barely sufficient) levels.  In fact, I often say that magnesium is the most important nutrient for practitioners to become savvy in using!  I have seen many people’s lives transformed by supplementing with that one nutrient.

In the summer, it’s a good idea to encourage clients to begin to get some wise sun exposure and get their Vitamin D naturally – from the sun.  Beyond digestion (pancreas/bile), absorption (intestines), and conversion (magnesium!), we need to remember that Vitamin D is a hormone and increase levels gradually – to allow the body’s receptors to respond and adapt.   The body also uses Vitamin A and Vitamin K in a trio along with Vitamin D to support the immune system.  Fat-soluble siblings.  But that’s another post for another day 🙂  If you want a deep dive on Vitamin D, check out this video.

I hope this quick clinical tip serves you and your patients and clients.  Follow-up questions are welcome!


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5 Questions for “Their Vitamin D Won’t Come Up?!”

  1. 3
    Renny says:

    Thank you so much Tracy I just had an ah moment. About a year ago my Vitamin D was at 30 mark and went on a journey to increase it. Recently I have been feeling unwell with a cough that doesn’t want to go and sleep which has gone terribly worse, as well as aches and pains. I went to do my extensive blood test, and have been searching for clues in there. I realized my Vitamin D is up to 40mark, but my Magnesium has now gone below the range, plus Co2 also low. I have been taking my normal magnesium supplements but was concerned how come it is so low. This Article now clarifies the relationship between Vit D and Magnesium. I have to get the levels up because now my Asthma attack is back and strong, thanks also to your Facebook pearls for this week I have made the full connection..
    And specific advise on dosages or any other thing I can do, much appreciated.
    I have started taking Magnesium glycinate over a week 3 times a day, including increase in magnesium rid has food. I wanted to also add Threonate for night time to help with sleep.
    Oxygen inhalation is now everyday. I am trying to eliminate all I think might be triggering the cough, I am about to change cleaning stuff… not bad at my food, but I think there might be GERD for sure…
    Wow think you for this information really, will help me heal myself and be a better coach.

  2. 2
    Tasia Wagner says:

    What type of magnesium do you recommend for supplementation? There are so many recommendations out there it’s hard to pick one…

  3. 1
    Mary says:

    Vitamin D at 5000iu or greater should also be accompanied by some K2, right? While the use of additional D uses up Mg, and Mg needs to be increased as you mentioned,would it not be prudent to also include K2 at the same time? to enhance calcium absorption into bones? And would enhanced bone absorption have a favorable influence on circulating Ca+ levels? I know you said A an K are for another discussion, but I tend to think of Mg, D, and K together. Thoughts? And if you have a redirect for K let me know.
    Thanks, Mary

    • 1.1
      SAFM says:

      I agree 100% about accompanying K2 with D for my clients who are about 40 y/o and older. When we are younger, we are likely to have more effective conversion of K1 to K2 in the body and less trouble with retaining bone density (due to lower oxidative stress and better hormone balance). I don’t think it would hurt to add for someone younger, but it may not be a supplement priority amidst other concerns for that age (e.g. antioxidants, essential fats, magnesium). Certainly there can be exceptions either way. Generally, the body regulates serum calcium fairly tightly with the coordinated action of parathyroid hormone and the excretion of excess calcium via the urine. This page has more information about Vitamin K2/K1 etc.:

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