HiAgain Myuser
yes , multivitamins have only 400 IU of Vitamin D per pill. That is a very low dose. IF you are deficient , you cannot build up your reserves on that amount. In fact , 375 IU daily, is recommended for a baby , ( IF exclusively breast fed , ) so, since you weigh much more , you need much more .
A good sunbathing session, but with no burning , can produce 10,000 IU to 20,000 IU in your skin . 20 mins of strong sunlight , on any particular area of skin will produce the maximum amount of vitamin D , for that day. So there is no point in baking for hours in strong sunlight. BUT be aware that suncream , factor 15 or above , will stop you producing Vitamin D in the skin , it absorbs the UVB light , which creates the Vit D. Many organisations now recommend that you leave off suncreams for 20 mins for that very reason.
The fact that you have already been shown to be deficient with Vit D once , and bearing in mind , that the human body requires approx 65 to 70 IU per kilogram of weight , per day , from all sources , sun , food and supplement, this might indicate that you are probably quite low. Low vit D has also been associated with anxiety/depression. Have a good read of that thread above. !
Good Luck .
BTBH.
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