The association between ultraviolet B irradiance, vitamin D status and incidence rates of type 1 diabetes in 51 regions worldwide

Diabetologia. 2008 Aug;51(8):1391-8. doi: 10.1007/s00125-008-1061-5. Epub 2008 Jun 12.


Aims/hypothesis: This study is an analysis of the relationship between ultraviolet B (UVB) irradiance, the primary source of circulating vitamin D in humans, and age-standardised incidence rates of type 1 diabetes mellitus in children, according to region of the world.

Methods: The association of UVB irradiance adjusted for cloud cover to incidence rates of type 1 diabetes in children aged <14 years during 1990--1994 in 51 regions worldwide was assessed using multiple regression. Incidence data were obtained from the Diabetes Mondial Project Group.

Results: Incidence rates were generally higher at higher latitudes (R2 = 0.25, p < 0.001). According to multiple regression, UVB irradiance adjusted for cloud cover was inversely associated with incidence rates (p < 0.05), while per capita health expenditure (p < 0.004) was positively associated (overall R2 = 0.42, p < 0.0001).

Conclusions/interpretation: An association was found between low UVB irradiance and high incidence rates of type 1 childhood diabetes after controlling for per capita health expenditure. Incidence rates of type 1 diabetes approached zero in regions worldwide with high UVB irradiance, adding new support to the concept of a role of vitamin D in reducing the risk of the disease.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Calcifediol / therapeutic use
  • Child
  • Diabetes Mellitus, Type 1 / complications
  • Diabetes Mellitus, Type 1 / epidemiology*
  • Diabetes Mellitus, Type 1 / prevention & control
  • Geography
  • Humans
  • Regression Analysis
  • Ultraviolet Rays*
  • Vitamin D / therapeutic use*
  • Vitamin D Deficiency / complications
  • Vitamin D Deficiency / epidemiology


  • Vitamin D
  • Calcifediol