Oats & breakfast cereals · Glycemic index

Does granola spike blood sugar?

Not much. Granola has a low GI of 53, and a 30 g serving (1 single-serve portion, about ¼ cup) has a low glycemic load of 10. Granola's oats, nuts and oil keep its average GI low, but it is dense in carbohydrate and calories, so the amount in the bowl decides its real impact.

Key numbers

Glycemic index: 53; Low GI
Glycemic load: 10; Low GL
Available carbs: 18 g; 2.2 g fiber
Serving: 1 single-serve portion, about ¼ cup; 30 g · ready-to-eat

GI vs GL for granola

The glycemic index (GI) compares how fast the carbohydrate in a food raises blood sugar against pure glucose (100), using a fixed amount of carbohydrate. The glycemic load (GL) adds the other half of the story — how much carbohydrate a normal serving actually contains: GI × available carbs ÷ 100. For granola: 53 × 18 g ÷ 100 ≈ 10.

That figure is an average reported in the 2021 international GI tables (“Granola, mean of 11 foods”). Eleven granolas averaged 53, but individual products vary with their sugar, nut and fruit content. Many people pour well over 30 g, and the glycemic load rises in step with the portion.

Eating a different amount? Work out the glycemic load of your portion.

How to eat granola with less of a spike

Use it as a crunchy topping on plain yogurt instead of eating a bowl of granola with milk.
Compare labels and pick the product with the least added sugar per serving.
Weigh a 30 g portion once so you know what it looks like in your usual bowl.

Other low-GI choices

Compare with

See all 67 foods in the glycemic index table

Frequently asked questions

What is the glycemic index of granola?

Granola has a glycemic index of 53, which is low. That figure is an average reported in the 2021 international GI tables (“Granola, mean of 11 foods”). A 30 g serving (1 single-serve portion, about ¼ cup) contains about 18 g of available carbohydrate, giving a glycemic load of 10 (low).

Is granola good for prediabetes?

Granola can work in small amounts, especially as a topping rather than a full bowl. Check the label for added sugar and treat about a quarter cup as the serving.

Is granola better than cornflakes for blood sugar?

On GI, yes: granola averaged 53 in the 2021 tables and cornflakes 80. Granola is much more energy-dense, though, so a small serving matters more than it does with lighter cereals.

Sources

GI values come from the international GI tables; carbohydrate and fiber per serving are calculated from USDA FoodData Central.

Data last checked September 30, 2026.