D3

D3 is cholecalciferol, the form found in most supplements. Doses are given in micrograms (µg) or international units (IU), where 25 µg equals 1,000 IU. DOSES SPAN A WIDE RANGE. The range runs from 10 µg to 125 µg per capsule. The figure is on the front, sometimes in both units. The daily intake stated on the pack should be followed. THE FORMATS. Oil-filled softgels are the most common, since vitamin D is fat-soluble. Drops can be dosed freely and are practical for small amounts. Tablets exist but are less common. PLANT-BASED OR NOT. Cholecalciferol is usually derived from lanolin in sheep's wool. Plant-based versions use lichen instead and are labelled as such. D3 + K2 is a separate shelf next to this one, for anyone wanting both in the same capsule. THE BRANDS. NOW Foods has the widest choice of doses, Osavi the plant-based ones, Life Extension and Swanson the higher doses.