"We showed that hypomagnesemia independently predicts[Diabetes Care 2012 Yusuke Sakaguchi]
the progression to end stage renal disease
in patients with advanced type 2 diabetic nephropathy" .
"Our findings suggest that magnesium supplementation
may be renoprotective in this population."
-- this could be how fructose causes kidney damage:
it creates insulin resistance,
which in turn causes magnesium resistance .