Revising for your Vitamin D test

Exciting November Time

Its a very awkward time of year for an athlete blogger to write about themselves. Training is a little bit monotonous, which I think can be a good thing, so theres not really much excitement to write about there. I could tell you all about how awesome my training is going, but I don’t see the point, how well training is going doesn’t matter, what matters is how high I jump in a competition. I could reel off test results and demonstrate my physical prowess, but again, would I just be setting myself up for a fall if it didn’t all come together in one spectacular vault competition? So for these reasons, and the fact that I would probably bore all three of the people who actually read this blog and lose 33% of my readership, I’m going to continue writing about vaguely related topics.

This week, funded by Welsh Athletics and the Welsh Institute of Sport, I received back my vitamin D test results. Pretty exciting stuff. At the same time we actually had a genetic test done for ACTN3 so when I get that result back, I’ll blog about that, but this week you get my poorly informed opinions on Vitamin D.

Vitamin D

So if you haven’t heard by now of the importance of Vitamin D, then where have you been? 

It seems to have all sorts of positive benefits ranging from improved immune function and chemo protection, to its role in regulating calcium usage in the body (think preventing osteoporosis and stress fractures), even improving brain function and some links to maintaining healthy weight, even more recently I read this study on Vitamin D making Leucine work better, so it could even improve performance more directly.

The problem

Vitamin D is formed in the skin when exposed to sunlight, or more specifically, the UV B range of wavelengths of sunlight react with an analogue of cholesterol to form Vitamin D. In case you haven’t noticed our country isn’t particularly sunny at the best of times, and September to April are certainly not the best of times. Interestingly UV A wavelengths actually breaks down the vitamin D, its like a natural way of regulating dosage.

So as an athlete what are our other options?

Sunbeds? Unfortunately in this country the UV B spectrum of the sunbeds is very low, so going on a sunbed say, once a week throughout the winter will do almost nothing for levels. Such a shame. Apparently, some hospitals have full-spectrum sun beds for Seasonal Affective Disorder (SAD) patients (it may be insensitive but I love that anachronism) but can’t imagine they’re easy to get access to.

So we’re left with supplementation. A D3 supplement in a fat filled gel cap seems to be the best absorbed in my experience. Theres many different recommendations out there on the web in order to get your levels up, theres also many warnings about needing blood tests to monitor your levels to prevent toxicity of dosing too high. However there seems to be very little reporting of anyone being able to achieve toxic levels and getting detrimental side effects.

I’ve had my levels tested twice, one time I was taking 4000iu per day and I still came in at low-normal levels. Last winter however I managed to get my levels measuring “off the scale”. Thats right, my levels were so high they couldn’t accurately test them. In fairness the test only measures up to 175 nmol/l and toxicity doesn’t really kick in until 250 nmol/l. This year, on the same protocol I tested at 170nmol/l, the tope end of normal, pretty much perfect if you ask me. I am however going to dial back my dose a little. So this is how I managed it:

My Vitamin D protocol

The first aspect was I switched from everyday dosing to 1 bolus dose a week. the research seems to say this helps you increase levels faster, and as its fat soluble, you don’t just pass the excess like say water-soluble Vitamin C, so you’re body drip feeds itself through the week. 

I also took this with a fatty meal to help absorption. 

I also upped my dose to 50,000iu per week. Possibly a little high, but I like pushing the boundaries.

Also, around the time of my weekly dose I would take a 6 minute sun bed. Now I know I said that sunbeds don’t produce the light spectrum needed to produce vitamin D, but this is just my way of trying to keep things as natural as possible. In case theres any co-factors or other things we don’t know about that work together with the Vitamin D which work through light exposure.

This is my protocol every week or two throughout the winter and it definitely keeps my mood up if nothing else.

Vitamin D from the sun


Getting your dosage from the sun is more difficult to calculate but definitely better for you. Production varies depending on amount of skin exposure, sun intensity and even your skin tone, darker tones needing more sun to produce similar levels (fancy that, nature figuring that evolution of darker skin means massive exposure to sunlight and it doesn’t want you overdosed on Vitamin D). But as a general rule of thumb, 1000iu can be generated on a summers day with 25% skin exposure, i.e. wearing shorts and t-shirt, in 19 minutes for the darker guys or only 5 minutes for you pasty fellows.

One other tip, if you’re lucky enough to be able to get your Vitamin D from sun exposure, make sure not to shower straight after. The vitamin is produced in the skin and its actually possible to wash it off before its absorbed, so leave it a good hour after coming in, or as long as possible to allow maximum absorption.

Also, don’t tan through glass, glass blocks the UV B and allows through the UV A, so can make levels worse. 


Vitamin D good, living in the UK bad

Supplements and sunbeds ok, sunlight better


2 thoughts on “Revising for your Vitamin D test

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s