As of 2010, the Institute of Medicine recommends persons aged 9 years to 70 years consume between 600 international units and no more than 4,000 international units of vitamin D per day, says WebMD. The daily recommended dosage varies depending on a person's age, weight and sun exposure.
There is some disagreement among medical professionals about the necessary daily dosage of vitamin D. Daily doses are different for infants, young children and the elderly. In addition to age, overweight people may require more vitamin D than leaner individuals, explains WebMD. With so much variance regarding the recommended daily dosage of vitamin D, it is important for each person to talk to his doctor about how much vitamin D he should take.