Click to listen to the audio…
When you’re insulin resistant, that is, you’ve got metabolic syndrome, pretty much every chemical in the body is NOT QUITE RIGHT. Some are up. Some are down. Few are actually at physiologically NORMAL levels.
Traditionally the focus is on the big guns.
- Sugar
- Insulin
- And cholesterol
In this series, we take a look at some of the other players.
Who they are, what they’re up to and how they’re part of the state of insulin resistance.
Vitamin D when you’re insulin resistant
Serum vitamin D levels are often lower, than ideal.
Now, although WE refer to vitamin D, as a vitamin, because we can get it in food, food is not the official source of vitamin D. We make it ourselves, in our skin. Basically we turn skin cholesterol, into vitamin D, when we expose our skin, to high enough levels of UVB.
Since we make it, it’s strictly speaking not a vitamin.
A more accurate, description of what vitamin D is, is it is a hormone. And as a hormone, it is a signalling molecule, signalling to pretty much every cell in the body, via the vitamin D receptor.
The evolution of a hormone
It turns out, what we make and or eat, which is also known as calciferol, in not quite a hormone, yet. In order to be one, a little chemistry has to happen.
Step number one, takes place in the liver. The liver pops a hydroxyl group onto the vitamin D, making it 25(OH)D. Now this is exciting, but not enough to make the vitamin D, a fully fledged hormone. To be a full fledged hormone, the kidney also has to pop on a hydroxyl group, to make 1,25(OH)2D.
Only then is vitamin D, ready to be a hormone…
Controlling the process
The first step in the process is not strictly controlled, but step two is, so your body makes sure you get, just the right amount of vitamin D.
The “right” amount, depends on your calcium status,
which is influence by your genes and lifestyle (environment).
Vitamin D in action
Now vitamin D, the hormone, works hard. Scientists reckon over 900 genes, take their orders from vitamin D, via the vitamin D receptor (VDR), and VDR receptors are ON virtually every cell in the body.
Something SO powerful, MUST BE a controlled substance.
Measuring your vitamin D status
The blood test that is routinely used, to test vitamin D status, is measuring how much pro-hormone is circulating, not how much of the active hormone is around.
This means,
- You could have low calcidiol but normal calcitriol or
- You could have low calcidiol, plus low calcitriol.
Only in one of these scenarios are you genuinely deficient.
When you’re sun deprived
You have low calcidiol, plus low calcitriol
In this is the case, you need more calciferol……
When you’re NOT sun deprived
But, before you reach for that vitamin D supplement, it is important to realize, just like you store calories for a rainy day, you also store vitamin D, for sun less days.
Something that is a reality, in winter, in many parts of the world and so something, Mother Nature, has a contingency plan, for.
The spot where the vitamin D is stored………………. fat cells.
So the more fat cells you have, the bigger your capacity to store vitamin D. In this scenario,
You have low calcidiol but normal calcitriol.
So you don’t need more calciferol !
Accessing your vitamin D stores
Having said that…………. to get the vitamin D out, is an active process. If you’re not in the habit of burning fat, which you’re not, when you’re insulin resistant……….odds are, you’re not releasing much of that vitamin D store.
When people lose weight, as a rule, their vitamin D status improves.
More might NOT be BETTER
The point being, adding more, of something you’re not short of, doesn’t make sense. And might in the long run, be harmful.
There are now half a dozen, clinical trails, that have shown, supplementing with vitamin D, does not improve body chemistry, in those who are not genuinely short of vitamin D.
The trouble with extra vitamin D
Too much vitamin D, can be just as big a problem, as too little, it raises the levels of calcium, circulating in your blood.
Now this calcium can be deposited in your bones, which is good.
But, it can also be deposited in your blood vessels, turning your blood vessels, to stone.
Inflexible blood vessels are unable to expand and contract as the blood whooshes round – this contributes to rising blood pressure levels and eventually pipe bursts. A problem, that goes hand in hand, with insulin resistance.
Know your vitamin D status
If you’re genuinely deficient, supplement to “fix” it. The universally agreed upon level, which is considered to be deficient, is a level of 25-OH D <10 ng/ml. At these levels, your blood levels of calcium, will be low (hypocalemia), and parathyroid levels will be elevated, putting your bones in jeopardy.
But, when your levels are not extremely low, the biology suggests that you should proceed with caution, you want enough vitamin D, not too little and not too much.
Sun before supplementation
The optimum way to improve your vitamin D status, is the way Mother Nature intended, through sun exposure.
Small doses of sun, are not risky – sun burns, are.
Exactly how much sun you need to turn up vitamin D production depends on your skin tone, how much of you is catching the sun, the season and your geography.
You can’t over do it. Excess vitamin D production by the skin, doesn’t happen.
And, since the sun does a whole lot more than just make vitamin D, the benefit to your body chemistry will be extend way beyond, vitamin D production.
No sun living
If circumstances make getting your vitamin D fix, from sun tanning, an impossible proposition. Then, “eat” it, foods considered high in vitamin D, include fish and eggs.
Plan C would be to take a supplement.
This should always be medically supervised and be focused on repleting vitamin D levels i.e. stop, when levels begin to rise, above normal thresholds.
Vitamin D and body chemistry
Epidemiological studies, do suggest, that running low on vitamin D levels, is a sign of bad body chemistry, but this does not mean, it is the CAUSE of bad body chemistry. Your vitamin D status, is a proxy for your overall health.
And you cannot fix it, by taking excessive amounts of a vitamin D supplement.
You need to “fix” the underlying body chemistry that is keeping it low.
NOTE : This might take a little detective work.
Vitamin D, just one of hundreds of things in the body that are amiss when you’re suffering from metabolic syndrome. To learn more about some of the other players, go to our “Ups and Downs” of Insulin Resistance series.
Ultraviolet radiation, vitamin D and the development of obesity, metabolic syndrome and type-2 diabetes. Photochem Photobiol Sci. 2017 Mar 16;16(3):362-373. S Gorman, RM. Lucas, A Allen-Hall, N Fleurya and M Feelischc
Vitamin D testing and treatment: a narrative review of current evidence. Endocr Connect. (2019) 8(2):R27-R43. S Pilz, A Zittermann, C Trummer, V Theiler-Schwetz, E Lerchbaum, MH Keppel, MR Grübler, W März, M Pandis
Vitamin D Toxicity–A Clinical Perspective. Front Endocrinol (Lausanne). (2018) 9: 550. E Marcinowska-Suchowierska, M Kupisz-Urbanska, J ?ukaszkiewicz, P P?udowski and G Jones
Further reading
Visit the vitamin D library page, for more stories, explaining why your vitamin D status, matters.
How much vitamin D do you really need ?
The idea that the modern world is running low on vitamin D is widely accepted, what is debated is what is NORMAL. Massai suggest normal is above 40 ng/ml.
Fat cells lock in vitamin D potentially short changing health in the overweight
Shortages of vitamin D are associated with poor health. Obesity is linked with vitamin D shortages. Is there a connection ?
Calcium supplements are building bones and breaking hearts
More of something is not always better – research suggests calcium supplements are packing too much of a punch leading to heart attacks and strokes