Hi Again ,
Ah, Now I see what you mean , You are asking if 3000 IU is a reasonable daily dose.
That is a really good question , the latest vitamin D research says that it is . Many of the older guidelines say that it is higher than strictly necessary , when all you want to do is maintain a blood level of 50 or just above. There is quite a controversy over that question.
For an adult , weighing about 75 kg, there is not reason to suppose it is harmful, indeed , you are likely to raise your blood level by 75 nmol/L , ( above your long term prevailing average level , when you are without supplementation.) IF you have rare conditions such as hyperparathyroidism, sarcoidosis , granulomatosis or Williams syndrome, or carcinoma, then do not take Vitamin D without medical supervsion.
IF you are treating yourself, then it makes good sense to check your current blood level, with a Vit D test, then decide what blood level you want , then take supplementation to achieve that. You will ON AVERAGE , raise your blood level of vit D by 25 nmol/L for every 1000 IU that you take as a long term , daily supplement dose. That is an average person , you may not be average, there is quite a variability in response to supplementation.
FOR that reason it is a really good idea to check your blood level about 3 months on a continuing daily dose. You level will then have stabilzed. It takes 60 to 90 days to stabilize.
The controversy is really about which blood level is a good level to aim at. The latest idea is around 100 nmol/L - 150 nmol/L , older guidelines are around 50 as a minimum, but accepting that 50 is ok. The latest vitamin D research points strongly to that figure being too low. IF you look at a lot of NHS guidelines you will often see 50 to 200 , as within the acceptable range. wheras , 100 -150 , is what vitamin D researchers think is likely to be the most applicable , for optimum health. Outdoor workers in strong sunshine , generally reach 120 - 140 . Some however will go as high as 200. That is why the NHS considers that figure acceptable as well, in some places. There is a great variability throughout the NHS , as to what will be recommended to you , whenever you ask a doctor, consultant or other practitioner.
You can get a vit D test from your doctor , if he agrees ( some won't ) or you can get tests here , by sending a sample of blood on blotting paper to this NHS lab. They will reply by email within a week. <a class="break-all" href="https://www.vitamindtest.org.uk/" rel="nofollow" target="_blank">www.vitamindtest.org.uk/</a> IF not doctor ordered they do charge £29.
I have posted quite a bit here on Mumsnet about vitamin D , have a look at some of my posts for further information , or just get back to me if you need any additional information.
Here are a couple of very long posts , but full of detail, about vitamin D and how people dosed themselves , why , what the their symptoms were , etc etc. I posted quite a bit there.
www.mumsnet.com/Talk/general_health/2841497-If-you-are-vitamin-D-deficient-what-have-you-been-prescribed
www.mumsnet.com/Talk/general_health/2421492-Vitimin-D-can-it-have-this-effect
Best of luck
BTBH
PS. 30 that you have seen in notes, might be 30 nmol/L i.e a blood level , often considered the borderline between deficient and insufficient.
when you see mg that is milligram , or might be microgram
1000 IU is 25 microgram. 30 microgram would be 1200 IU.
Somewhat confusing I know. Remember, just 1 milligram would be 4000 IU .
A dose of 500 IU , won't do much , it would increase your blood level ON AVERAGE , by 12.5 nmol/L.
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