1 · Eat
What's on the plate is what comes in
The carbohydrate in rice, noodles and bread is what glucose is made from. Protein, fat and fiber come in with it.
CarbsProteinFatFiberSame colors as the pond
2 · Digest and absorb
Carbs are broken down into glucose
In the stomach and intestine, carbohydrate turns into glucose and passes through the gut wall into the blood. Protein, fat and fiber slow this flow down a little.
3 · Blood
Glucose rides the blood around the body
Absorbed glucose is carried in the blood. The more carbohydrate you eat, the more glucose there is, and the curve is drawn higher and longer.
4 · Insulin
Insulin opens the doors
As glucose in the blood rises, the pancreas releases insulin. Like a key, insulin opens the doors of muscle, liver and fat cells so glucose can get in.
5 · Store
What isn't used gets stored
Glucose that gets in is used for energy, and the rest is stored in the liver and muscle. When those stores are full, the remainder is stored as fat.
6 · Recap
So the one thing you can change is how much you eat
Digesting, absorbing and storing are things your body does on its own. What you decide is how much goes on the plate.
Change it and the current picture changes too.
Why the curve differs from person to person
Even with the same meal, how much insulin is released and how easily the doors open differ from person to person and from day to day. Sleep, stress, exercise and how you feel also play a part.
With diabetes, the body may make little insulin (type 1) or the doors may not open easily (type 2), so glucose can stay in the blood longer. During pregnancy the doors can open less easily for a while (gestational).
This picture is simplified for education and cannot be used to judge anyone's condition or decide on treatment. Please talk to your care team with any questions.
What this picture is based on
Glucose uptake and storage driven by insulin follow the standard account in endocrine physiology — Guyton & Hall, Textbook of Medical Physiology, metabolism and endocrinology chapters.
The picture is reduced to five steps and does not reproduce real values. The curve has no scale; it shows shape only. Some paths, such as glucagon, the kidneys and the brain, are left out.
This diagram is a simplified educational reference on nutrient metabolism and does not replace medical diagnosis, treatment or prescription.