what is larger mcg or mg
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. 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.