James,
Even if you did not eat anything after your night shift work, you would still get a high blood sugar reading. Why? Because the liver will release glucose from storage. Having some weetabix and a small piece of ginger cake were not the real cause of your bs highs. But they surely played a minor role.
Since my diagnosis as a type 2 diabetic in July 1991 (my first blood sugar reading was 468 mg/dl), I have always been on HCLF diet. Yes, all of my fasting and post-meal blood sugar readings have consistently been high. Why have they not harmed me yet? Maybe because I run the stairs 4 times per day, a total of no less than 1 hour per day. I burn all the glucose that I have taken in. My weight is steady from 137 lbs to 143 lbs. My height is 5'7". I have never been on any anti-diabetes drugs.
Bonny Damocles
Male, 81 years old
I am not on any pharma drugs for any health problems
I think that I am the first untreated 25+year T2D with no D complications