Well, I guess like anything we eat, our individual tolerance of a food can be measured either by a blood glucose meter, or a CGM device. No one size fits all.
@PatsyB , as you are on insulin, are you counting carbs and dosing accordingly? I feel uneasy discussing with you as I have T2, but not on insulin, and we do have to be aware of different forms of management.
I think a banana weighing 100gr, has about 25 gr carb, though that could vary, ripe bananas apparently higher carb than green bananas. Some people carry glucose to treat a hypo. Your choice of hypo treatment, a banana, if that suits is fine. Are you getting BG and HbA1c levels that are within targets set,
@PatsyB?
As for your question, I do eat banana, sometimes. I avoided them for several years, due to following low carb method of eating. The last 18 months or so, I have been quite ill, and waiting for treatment / surgery for hyperparathyroid and hypercalcaemia. Sometimes I have such abdominal pain and sickness that I have to eat the BRAT diet for several days. This is Banana, rice, apple sauce, toast. This happens for a few days every couple of weeks. Banana and toast being a particular favourite. My HbA1c has dropped and so has my weight. Currently banana does not seem to spike my BG . Though I would emphasise, this may not be the same for others