Ecological studies of the UVB-vitamin D-cancer hypothesis.
OBJECTIVE
This paper reviews ecological studies of the ultraviolet-B (UVB)-vitamin D-cancer hypothesis based on geographical variation of cancer incidence and/or mortality rates.


METHODS
The review is based largely on three ecological studies of cancer rates from the United States; one each from Australia, China, France, Japan, and Spain; and eight multicountry, multifactorial studies of cancer incidence rates from more than 100 countries.


RESULTS
This review consistently found strong inverse correlations with solar UVB for 15 types of cancer: bladder, breast, cervical, colon, endometrial, esophageal, gastric, lung, ovarian, pancreatic, rectal, renal, and vulvar cancer; and Hodgkin's and non-Hodgkin's lymphoma. Weaker evidence exists for nine other types of cancer: brain, gallbladder, laryngeal, oral/pharyngeal, prostate, and thyroid cancer; leukemia; melanoma; and multiple myeloma.


CONCLUSIONS
The evidence for the UVB-vitamin D-cancer hypothesis is very strong in general and for many types of cancer in particular.
Sunlight, Nutrition, and Health Research Center, P.O. Box 641603, San Francisco, CA 94164-1603, USA. wbgrant@infionline.net
William B
WB
Grant
D004784:Environmental Monitoring; D006801:Humans; D009369:Neoplasms / Q000209:etiology*; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014808:Vitamin D Deficiency / Q000209:etiology*