Patients need vitamin D which is normally produced in the skin in response to ultraviolet light from the sun. Vitamin D is important for calcium absorption and good bone health. Physicians have been using sunscreens to protect patients from skin cancer and the aging effects of sunlight for a least a half a century. Dermatologists have promoted sunscreen use to restrict sunlight exposure especially in white Caucasians. If this behavior is done 100% of the time when outdoors individuals may suffer from vitamin D deficiency. It is impossible to influence persons' behavior to wear sunscreens all the time when outdoors. With the use of sunless tanning agent (DHA), once a week, we can obtain a continuous sunscreen in the top layer of the skin that will not wash off, can't be removed with soap and water, or removed by perspiration. Under these circumstances we can answer the scientific question, will sunscreen use inhibit the production of vitamin D in the skin?

Inclusion Criteria:

• males or females
• ages 19-50 with less than 16 oz milk per day
• less than 10 hours of sun per week
• no Vitamin D supplements
• no anticonvulsants
• no barbiturates
• no steroids
• no meds that increase photosensitivity
• no granulomatous disease
• no liver or kidney disease
• no history of skin cancer
• BMI less than 30
• skin types I & II

Exclusion Criteria:

• None