Dietary intake of carotenoids and risk of type 2 diabetes
Sluijs I, Cadier E, Beulens JW, van der A DL, Spijkerman AM, van der Schouw YT
December 2014
http://www.nmcd-journal.com/article/S0939-4753(14)00373-1/abstract

In this prospective study among 37,846 men and women followed-up for a mean of 10 years, higher dietary intakes of b-carotene and a-carotene were associated with a reduced diabetes risk, whereas dietary intakes of other individual carotenoids were not associated with diabetes risk.