"Type l diabetics should not be fasted according to many experts, however some allow fasting as long as glucose levels are tested frequently and insulin intake adjusted according to lowered needs during a fast. Type ll diabetics should also be checked regularly, and they will probably find that Sugar
levels are normalised during the fast. "
"Kidney failure is thought to be a sound reason for avoiding fasting since the process makes excessive demands on remaining kidney function. However under controlled conditions short fasts can be helpful in such cases"
diabetics have kidney issues. the first phase is "silent" meaning the damage could be occuring without outward signs.
"There are strong contraindications to even short-term fasting for anyone who is taking prescription drugs. If a health condition is such as to warrant regular intake of such medication then the condition should be treated in such a way as to avoid long fasts or unpredictable reactions could occur. This is particularly true of anyone taking steroid medication, or who has taken steroid medication in the past for long periods. A similar caution is required regarding anyone taking forms of hormone replacement, such as in cases of underactive thyroid.
In all such cases (where steroid - hormone medication is current of has been prolonged) supervision of the fast is essential, in a controlled environment - clinic, hospital etc. whether or not weaning from the medication has been possible prior to the fast. "
there is more to read in the link. its a long post but its laid out really well. you can skim thru it easily by reading first line of a paragraph to see if the info is something you can use or learn from. or if you can skip onto the next paragraph for more info