For adults, the 5-μg (200 IU) vitamin D recommended dietary allowance may prevent
osteomalacia in the absence of sunlight, but more is needed to help prevent osteoporosis and …

Vitamin D has captured attention as an important determinant of bone health, but there is no
common definition of optimal vitamin D status. Herein, we address the question: What is the …

The objective of this review was to apply the risk assessment methodology used by the Food
and Nutrition Board (FNB) to derive a revised safe Tolerable Upper Intake Level (UL) for …

Background: Currently, there is a lack of clarity in the literature as to whether there is a
definitive difference between the effects of vitamins D 2 and D 3 in the raising of serum 25-…

The report by Hyppönen and Power in this issue of the Journal (1) highlights a frustrating
and regrettable situation for nutrition researchers. In the early 1970s, the same serum 25-…

In all species tested, except humans, biological differences between vitamins D 2 and D 3
are accepted as fact. To test the presumption of equivalence in humans, we compared the …

Background: The Food and Nutrition Board of the National Academy of Sciences states that
95 μg vitamin D/d is the lowest observed adverse effect level (LOAEL). Objective: Our …

The physiologic range for circulating 25-hydroxyvitamin D3 [25(OH)D; the measure of Vitamin
D nutrient status] concentration in humans and other primates extends to beyond 200nmol/…

Supplemental vitamin D is available in 2 distinct forms: ergocalciferol (vitamin D 2 ) and
cholecalciferol (vitamin D 3 ). Pharmacopoeias have officially regarded these 2 forms as …

Vitamin D requirements are thought to vary with age, but there is little comparative evidence
for this. One goal in establishing a vitamin D requirement is to avoid secondary …