The team from Warwick University tested the effect of vitamin B1, which is found in meat, yeast and grain, on 40 patients from Pakistan.
The treatment stopped the loss of a key protein in the urine, the journal Diabetologia reports.
Charity Diabetes UK called the results "very promising" - but said it was too early for any firm conclusions.
The latest findings build on earlier work by the Warwick University team, showing that many diabetes patients have a deficiency of thiamine.
According to the researchers, this cheap and readily available supplement could benefit most people with diabetes - both type 1 and type 2 - as between 70% and 90% of people with diabetes are thiamine deficient.
In diabetes the small blood vessels in the body can become damaged.
For more on this article, please click on the following link: Thiamine 'reverses kidney damage' : BBC