A daily dose of vitamins has recommended and upper tolerable limits for each of 24 nutrients established by the Institute of Medicine, according to WebMD. For example, adult males should take 3,000 international units per day of vitamin A, while women should take 2,310 IU per day.
For men, the daily dose of vitamin B3, or niacin, is 16 milligrams per day, while women need only 14, based on the chart posted by WebMD. The need for vitamin B6 varies between 1.3 and 1.7 milligrams per day, depending on age and sex. Men need an intake of 90 milligrams per day of vitamin C, and women need 75 milligrams. Adults up to the age of 70 should aim for 15 micrograms per day of vitamin D, or calciferol, and all adults require 22.4 IU per day of vitamin E, which is also known as alpha-tocopherol.