Same food, different reaction?

The overall impact is how many carbs we eat, but it is influenced by exercise, the amount of fat in the meal, alcohol, infections, first thing in the morning the dawn phenonomen, among other things.

@tiredgirl91 are you sure it is the food that is causing the morning spike?
Our blood sugars are affected by many things. This article lists 42 factors that can affect them.

It is common to be more insulin resistant in the morning as our helpful livers dump glucose.
But it could also be something like having a bad night's sleep or doing more exercise in the afternoon or having a stressful meeting in the morning.

The only way you will experience exactly the same reaction to the same food is if you eat it at the same time, go to bed at the same time, do the same amount of exercise at the same time, live in a sealed bubble that controls the air that you breath, have no hormonal changes, ...