Insulin index
En bref
A measure of the insulin response caused by a food, which can differ from its glycaemic index, showing that some foods stimulate insulin without sharply raising blood sugar.
The insulin index (II) measures how much a food raises insulin, independently of its effect on blood sugar. It is compared with a reference food (often white bread = 100).
The original angle (the insulin/blood sugar gap): intuition says “little sugar = little insulin”. Wrong for some foods. Surprising cases where the insulin index exceeds the glycaemic index:
- Dairy products: milk and yoghurt have a low GI but a high insulin index (2-3× their GI). Milk proteins (especially casein and whey) strongly stimulate insulin. This is beneficial for building muscle, but worth knowing about for people with diabetes
- Meat and fish: a GI of 0 (no carbohydrate) but they still provoke an insulin response (protein stimulates insulin)
- Some protein + fat foods
Why it matters:
- For someone with type 1 diabetes, calculating insulin doses from carbohydrate counting alone may not be enough, as protein counts too
- As insulin is a storage hormone, understanding the insulin index fine-tunes weight and fullness management
- It explains why a “low-sugar diet” that is rich in dairy can still stimulate a lot of insulin
A caveat: the insulin index remains a specialist tool, less practical than the GI because little data exists. It enriches understanding but does not replace the basic principles (whole foods, balanced meals).
Put it into practice
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