You’ve been diagnosed with gastroparesis? What treatment plan?
Edit: asking because yes, poor glucose control is associated but if a doctor is managing your care—particularly diet modifications and current meds—they would be the best to discuss this with and should know you’re doing IF.
At the same time, it’s really difficult for us to know ourselves when food has passed the duodenum and absorption does continue after it has. Heathy people can take 8hr to “digest” what they’ve eaten. It’s not abnormal to take at least 4hrs. The whole process actually takes well over a day. What you’re eating is a major factor, particularly fiber content (and fiber type). So if this isn’t an actual disorder, you could eat food that’s “faster” to digest, but of course that’s also going to spike insulin, versus eating food that’s associated with a gradual rise and fall.
If you’re curious, and have some extra money to burn, you can get a glucose kit and test your blood sugar levels.