Re: Eating before blood test
There is a test called an HbA1c, or glyco-hemoglobin or A1c for short, that measures the the average blood sugar over the past 8-12 weeks. It does not require fasting. Recently a symposium of endocrinologists has recommended that this test be used for diagnosing diabetes. I would call his doctor tomorrow and ask if they can do that.
At his age, I would definitely NOT have him fast, especially not for that length of time. If they can do the A1c, he would be able to eat anything he wanted to the day of the test.
If they insist on doing a fasting blood glucose test, then they should make an appointment for earlier in the day, even if they can't fit him in for a few weeks.