Hi babieseverywhere ,
From your posts these few things may be helpful to know...
You can bypass your gut malabsorption by taking Vitamin D as an Oral spray , which is absorbed directly into the bloodstream.
There is a 6 to 1 variation in the response to supplementation. i.e. people are very different. Reasons are varied, but can be gut problems, genetic variability, efficiency with which the liver transforms VitD3 ( the supplement) to the compound which is measured in the blood ( calcidiol) by your doctors tests and so on. BMI can have a dramatic effect upon the level your blood calcidiol level reaches with any given dose of supplementation. This is because VitD is fat soluble , hence the desirability of testing your level . Do not just assume that such and such a dose will have such and such an effect. As mentioned there is a 6 to 1 variability in response. I have outlined the average response ... you may not have that response.. as your pharmacist thought !
An average person will increase their blood level of calcidiol ( i.e. 25hydroxyD3 ) .... by 25 nmol/L if they supplement with 1000 IU daily ...over the long term.
It is better to dose daily: this is because VitD3 ( the supplement ) is used by your cells as well as the blood storage form 25hydroxyD3. When you have a low blood level such as yourself , your body ( liver) quickly transforms the VitD3 into 25hydroxyD3, such that within 3 days the VitD3 form is almost entirely gone ... i.e.the half life is 24 Hrs.
More than likely you will need to supplement with oral spray with say 6000 IU per day , this will increase your blood level reaching an equilibrium level in about 60 to 90 days , you should then retest your blood level . The test actually measures the level of 25hydroxyD3 ( calcidiol) in your blood in nmol/L . Your level should be 100 or more, this is a natural normal level , it is accepted as normal by the NHS , because humans that live outside a lot in a sunny climate reach that level. Unfortunately the NHS also accepts 50 as normal , it is not , it is distinctly too low. Some sectors of the NHS now accept that at least 75 is necessary, so at least some improvement. Many vitamin D researchers have concluded that a level between 100 and 150 is optimal.
My advice would be to get your level checked after prolonged supplementation as outlined above. If the doctor won't test, then you can get a test here <a class="break-all" href="http://www.vitamindtest.org.uk/index.html" rel="nofollow" target="_blank">www.vitamindtest.org.uk/index.html</a>
It is an NHS Lab at Sandwell hospital, they will do tests ordered by the general public, but if not doctor ordered they charge £28. It is a blood spot, you send to them on their test kit, the result is emailed back within a week.
IF you simply stop supplementation after a few weeks then your Vit D level will fall unless you make lifestyle changes....i.e. go outside in sunshine in the middle of the day ... for at least 20 mins. In the UK, sun is only strong enough between mid-April and mid-October. In the winter the UVB radiation is absorbed by the atmosphere. So there is a 6 month period in which you cannot make vitamin D in your skin.
Your gut malabsorption will not have any effect upon skin made Vit D , it passes directly into your bloodstream from your skin , and then your liver. So you can make it from sunlight. However - whenever the suns elevation is below 45 degrees , the suns UVB is absorbed by the atmosphere. This means that even in summer , early morning , or evening sunshine does NOT contain UVB.
SAFE and moderate use of sunbeds with some UVB output ( not all sunbeds have UVB ) would be another avenue for you if the other options fail.
Well, I hope all that is useful. !
Best of luck
BTBH
PS. I have posted quite a bit here on Mumsnet about VitD , search my nick , and you should find lots of other interesting info there as well
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