Availability of Vitamin D in Orange Juice

Inclusion Criteria: * Male and female adults of all races ages 18 years and older Exclusion Criteria: * Pregnant and lactating women * History of chronic severe liver (as defined by liver function test greater than 2 times upper limit of normal)or kidney disease as defined by a serum creatinine \>2.5. * History of taking a daily supplement that contains 400 or more IU vitamin D2 or vitamin D3 within the past month or taking a pharmacologic amount of vitamin D2 or one of the active vitamin D analogs including Zemplar (Paricalcitol), Dovonex (calcipotriol), Hectorol (vitamin D pro hormone) * Subjects who are taking orally Dilantin or glucocorticoids. * Exposure to a tanning bed or tanning on a beach for more than eight hours within the past month. * Subjects who drink more than 2 glasses (16 oz) cups of milk a day. * Known history of elevated calcium. (\> 10.5 mg% (mg/dl)) * History of intestinal malabsorption (i.e. Cystic Fibrosis, Fat malabsorption Syndrome, Crohn's Disease) * Allergies to orange juice * Any medical conditions in which it is not advisable to receive one 8 oz. glass of orange juice per day. * Currently taking, or having taken less than one month prior to start of study, a prescription vitamin D * Unwilling to consent to this trial