A Viridian Nutrition guide to nutritional measurements
Gram – A gram is a metric measurement of weight.
An old imperial measure of weight is the ounce and one ounce = 28.4 grams.
Milligram – One milligram is one thousandth of a gram and one thousand micrograms.
A milligram is generally abbreviated as mg.
Microgram – One microgram is one millionth of a gram and one thousandth of a milligram.
It is usually abbreviated as mcg or ug. Mcg and ug are the same.
But what about IU?
IU – the IU is an International Unit, usually used to measure fat soluble vitamins including Vitamin A, D and E. The conversion of IU to mg varies depending on the nutrient.
Vitamin A – One milligram of beta carotene = 1667IU of Vitamin A activity.
15mg of beta carotene = 25,000IU of Vitamin A activity.
Vitamin E – One milligram of vitamin E = approx. 1.21 to 1.49IU (depending on the carrier).
400IU of d-alpha tocopherol = 268mg.
Vitamin D – One microgram of vitamin D = 40IU.
400IU of vitamin D = 10ug.