Vitamin Guides

Vitamin labels change units without warning. The same nutrient appears as international units on one bottle and micrograms on the next, and because both are in circulation, two products can look wildly different while being the same strength — vitamin D at 1,000 IU and 25 mcg is the clearest example, and one of the most common misreadings in the shop.

The second variable is form. Folate appears as folic acid or methylfolate, B12 as cyanocobalamin or methylcobalamin, vitamin E as natural or synthetic, vitamin D as D3 or D2. These are named in brackets on the supplement facts panel rather than on the front, and they account for much of the price spread between products that otherwise look identical.

The third is serving size. Multivitamins in particular frequently count two or three tablets as a single serving, and every figure on the panel refers to that serving — so a product that appears more complete may simply expect you to take more of it.

These guides cover the conversions, the forms, and how to read a panel carrying twenty nutrients at once. When you are ready to compare products, the vitamin comparison filters by strength, form, format and brand.