US Professor Philip Raskin, who will lead the study at the UT Southwestern Medical Center in Dallas, Texas, said: “If you could prevent development of diabetes that would save people a lot of anguish and diabetes medication cost.”
The four-year trial across America will track 2,500 people age 30 or older who have pre-diabetes – a precursor to diabetes where blood glucose levels are higher than normal.
They will be given daily doses of vitamin D about five times higher than usually recommended.
Dr Raskin said: “The side-effects of vitamin D3 in the doses we’re going to use are few. It’s a fairly safe and inexpensive treatment.”