I discovered I was seriously deficient at 29 ng/ml. The healthy range recommended by the organisation is 40 - 60 ng/ml.
Six months later, I managed to persuade my haematology specialist to include serum vitamin D levels in the battery of tests he performs every 6 months or so.
The results came back this week and I wanted to share the improved result and what steps I took to get there. For an explanation on why I have these tests done at all, read here (hint: I don't think there's anything wrong with me.)
The advice of Grassroots Health was to supplement with 1000 ui of vitamin D for every 10 ng/ml of deficiency.
The PlanWith the British Summer just starting, I wanted to combine supplementation with some serious (but careful) sun worshipping. I had been reading that sun exposure without burning was perfectly safe and was looking forward to replacing my lily-white appearance borne of years of sun-phobia with a healthy tan.... not to mention replacing the evil sun tan cream with appropriately-timed donning of lightweight sleeves, scarves and hats.
The ResultThe result of my latest test came back at 53 ng/ml - an increase of 24. This is nicely in the upper regions of their stated sweet spot, which is good news.
The specialist's letter informed me that this is in the 'normal' range of 10-60. To be fair, this in no way implies this is the healthy range - but I can't help thinking that a level of 20 would not have sounded alarm bells.
So what did I do in the 6 months between tests?
What I DidI took 3000 ui of vitamin D3 on every day I did not sunbathe.
Over the summer in the UK and for one week on holiday in France I estimate I had 15 days of sunbathing in strong sun. I always avoided burning. On these days I did not supplement.
As my tan increased, the time I could spend in the sun increased - but a tan diminishes the manufacture of vitamin D by the skin, so I assume that by getting as much sun as I could safely get on any given day, I was getting as much vitamin D as my body could produce.
On sunbathing days, I always avoided washing all but the important parts with soap next time I showered (see this Dr Mercola Video for why).
Advice May Underestimate the DoseI believe that for me, a little more than 1000 iu is required to increase the serum levels by 10 ng/ml - I consistently took 3000 iu on non sunbathing days and would expect the sunbathing days to have far exceeded that dose... yet my blood levels were increased by only 24 (not 30 as Grassroots' advice would suggest.)
Winter PlanOver the summer I got a lot of incidental sun on the non-sunbathing days, simply by walking outside. This winter, any sun I get outside will be very weak and produce little or no vitamin D. On that basis, I plan to increase my daily dose to 4000 iu to compensate and hopefully maintaining my current level.
Stronger Immune System?This year has seen me treat my health with less respect than the previous 3 years put together - for example, this and this :-(
...yet I have still not been ill. Previous years have taught me to know when I am pushing it too far. By those standards, by now I should have had a cold.
ConclusionTwo things have changed this year. First, the vitamin D. Second, I have been doing even fewer, even shorter, but still highly intense workout sessions. My failure to get ill could be due to one of these factors, the other, or both. Or neither. Such are the vagaries of anecdotal reporting.
I will get re-tested in 6 months and report back.
My Yellow Skin Mystery
My Wheat Experiment
My Wheat Experiment Blood Test Update
My Vitamin D Defficiency