New research in the science journal Cell indicates that in animal studies a period of extreme fasting for five days (which in humans would be 800-1100 calories a day) followed by 2-3 weeks of normal food consumption (2000+ calories) can trigger a feast-famine response in the body. This response has been shown in previous studies to reduce some of the effects of aging, but new research now indicates it can force the pancreas to regenerate Beta Cells, which are the insulin-secreting cells in the pancreas.
This means that this could potentially be used as a future treatment for Type 1 diabetes and some variants of Type 2 diabetes. Though, obviously, how to get a diabetic individual to go on a fasting diet without having dangerous short-term consequences on blood sugar is a major concern.
The journal article detailing the new research can be found here:
http://www.cell.com/cell/fulltext/S0092-8674(17)30130-7There was also a human study on a much smaller scale that showed similar findings earlier this month:
http://stm.sciencemag.org/content/9/377/eaai8700
