I think they say a minimum of 4 tests per day is needed to keep a reasonable control of type 1 but more often has got to be better . Testing before a meal and then 2 hours later is the usual .
The advice I was given was to test just before going to bed, before eating, before driving (and every 2 hours whilst driving) plus any time you feel "off". I also test before and after exercising.
I have always thought of it as testing when I have a purpose
- before driving - DVLA requirement
- before eating - to calculate bolus dose with food, including correction dose
- before going to sleep - to ensure your levels are ok overnight.
- if feeling "off" - to check you are not too high or hypo
- before exercising - to check not too low
- after exercise - to check not falling too fast
Testing 2 hours after eating is a type 2 advice. Given that fast acting insulin lasts 4 hours, testing after 2 hours gives a false impression unless you are able to calculate insulin on board. So, what is the purpose? I would not correct and finger prick testing does not give enough information to change the pre-bolus time.
If you eat three meals a day, do not drive or exercise, that will be 4 times per day.