“When buying a vitamin D drop, you should look for the concentration of vitamin D in each drop, expressed as 'international units' or short-form IU. People need about 600-800 IU on a daily basis. With ...
Participants were randomized into one of four groups, receiving either 200, 1000, 2,000, or 4,000 international units (IU) per day of vitamin D3 supplementation. Blood levels of the markers of ...