Vitamin D’s role in health has been re-examined seriously over the past few years, and it is clear that the usual recommended doses are totally inadequate. The major students of vitamin D report that up to 10,000 IU daily is safe and that most people will need between 2000 and 4000 IU per day, except in the summer when there is some ultraviolet, and in warm sunny climates. Initial evidence suggests that it may be one factor in the genesis of Seasonal Affective Disorder (SAD).
Many mothers have been afraid to expose their children to the sun because of its supposed effect in causing skin cancer. As a result, 80 cases of rickets were reported in Canada over the past two years; this is a disease that was prevented for many generations because mothers consistently gave their children cod liver oil, which contains vitamin D as well as A.