Now Foods Chewable Vitamin D-3 1000 IU - 180 Chewable Tablets Now Foods Chewable Vitamin D-3 1000 IU supplies recommended levels of this key vitamin in a tasty chewable form. Vitamin D is normally obtained from the diet or produced by the skin from the ultraviolet energy of the sun. However, Vitamin D is not abundant in food. As more people avoid sun exposure, Now Foods.