The RDA is 600/800iu a day.but 2000iu is safe enough...
Walshie said his sister moved to California and was applying sun cream everyday and suffered from low vitamin d and was or is still I'll from lack of it..
Have a read of this mate..released 1 day ago..
https://www.nutraingredients.com/Article/2020/12/21/Experts-send-Vitamin-D-and-Covid-19-open-letter-to-world-s-governments