Type 1 diabetes starting to decrease in Finland, they started Vitamin D fortification in 2003
Incidence of Type 1 Diabetes in Finland JAMA letter to editor
Incidence per 100,000 children < 15 years
2006: 64.9
2011: 64.3
Bigger decrease for children < 4 year
- all of their life, as well as gestation, has been with vitamin D fortification

Study reported by Vitamin D council behind a $5 paywall?
See also VitaminDWiki
- Improved health due to vitamin D fortification in Finland
- Finland added vitamin D fortification to milk ( 20 IU per 100 grams ) and margarine in 2003
Danish study of childhood diseases vs vitamin D fortification – May 2013
_ _ items in both categories Diabetes and Child
Type I Diabetes stopped increasing in Finland after Vitamin D levels were raised – July 2014
Note: T1 Diabetes in Finland is still 5X higher than it was back when they gave an adequate amount of vitamin D to everyone.