Blood tests proved i have Vitamin D deficiency

It all depends where you are Probably the best quality high dose are Dekristol but in the UK I think they must be obtained with a prescription. They are German-manufactured and contain peanut oil - so if nut allergies are an issue are not for you. They come as 20,000 IU doses - possibly the only one available.

I have always used the supplements from Holland and Barrett in the UK - and they have been fine. Their high dose tablets are 1,000 IU but are tiny tablets and very easy to take up to 10 of them at once. The general advice is not to buy from companies you have never heard of and to avoid Chinese manufactured supplements. 

 

PS, I forgot to say, because vit D is not classified as a drug it is not subject to the same licensing regulations as pharmaceuticals. There are warnings on the internet about this but it will apply to any such supplement so is not particularly meaningful. That is the reason for my warning about sourcing them - a reliable supplier is essential.

You really need to stay in the sun for just fifteen minutes a day with lots if skin showing, as you should not have any sun screen as it will block the vit D. You may have an increase in your vit D blood levels in that time, I would have thought.

ptolemy has told you the getting vit D from sun bit - but the part that is missing is that the mechanism in your skin that forms vit D from cholesterol under the action of sunlight striking the skin at above a certain angle may not be functioning well enough to do the job. It falls off as we age, being about a quarter of the level at 70 that it was at 20 - and even at 20 it may be poorer in some people than others. The bit about the angle it hits the skin at means that in the UK it only works between 11am and 3pm from May to September. Outside those hours and months you could spend all day in the sun and very little would be made.

A high reading over around 150 can mean you may be vulnerable to vit D toxicity. This a build up of calcium, if your doctor is happy, things should be fine. If you stop the supplements that should solve the high levels. 

You use some vit D every day - no supplements should allow the level to fall slowly. Taking supplements the body stores the lot, when you stock up on vit D via sun there is a mechanism to stop after a certain amount is made (if you get to that much, which you obviously weren't!). If you are in the northern hemisphere your vit D level will be at its lowest in April - none made during the winter and still using it every day. So checking it in October and April is sensible - if it is lowish in October you'll need some supplement over the winter. In the southern hemisphere it is the other way round - high in April, low in October.