Oatmeal (rolled oats, cooked): GI, GL, Carbs & Blood Sugar Impact

Glycemic index of rolled oats (55), glycemic load, carbs per cup, instant vs rolled oats, and diabetes-friendly oatmeal.

Category: Grains & Starches · Nutrition data source: USDA FoodData Central · GI source: International Tables of GI & GL Values / University of Sydney · Last verified:
55 Glycemic Index Moderate
13.4 Estimated GL 1 cup cooked with water (234 g)
28.3 g Carbohydrate per 1 cup cooked with water (234 g)
4.0 g Fiber per 1 cup cooked with water (234 g)

Does Oatmeal Raise Blood Sugar?

Rolled oats cooked with water carry about 28 g of carbohydrate per cup with a published GI around 55 — moderate, with real fiber. The trap is the versions around it: instant/quick oats test considerably higher, and sugar, honey and dried-fruit toppings add a fast carbohydrate hit.

How to Eat It

Rolled (not instant) oats, cooked with water or milk, topped with berries and nuts rather than sugar and syrup. A normal bowl fits most diabetes-friendly plans.

Nutrition Facts (Oatmeal (rolled oats, cooked))

NutrientPer 100 gPer serving
Calories71 kcal166 kcal
Carbohydrate12.1 g28.3 g
Fiber1.7 g4.0 g
Sugars0.3 g0.7 g
Protein2.4 g5.6 g
Fat1.5 g3.5 g

Source: USDA FoodData Central, record FDC ID 173905 ("Cereals, oats, regular and quick, unenriched, cooked with water (includes boiling and microwaving), without salt"). Values may differ from brand-specific products.

Glycemic Index

Published GI: 55 (typical value).
Reported range: 55-83.
Evidence level: Moderate.
Note: Rolled oats test around 55; instant/quick oats test considerably higher (75+).

Sources: International Tables of Glycemic Index and Glycemic Load Values (2008/2021); University of Sydney GI Database (glycemicindex.com). GI values are reported relative to a glucose reference.

Learn more: What is GI? · What is GL? · GI vs GL

Estimated Glycemic Load

GL ≈ 13.4 per 1 cup cooked with water (234 g).

Calculation: GI (55) × available carbohydrate per serving (24.3 g = 12.1 g − 1.7 g fiber) ÷ 100. Calculated by DMSafeHaven; formula per standard published GL methodology.

Diabetes consideration: Rolled oats in a normal serving are a moderate, fiber-carrying breakfast - the instant varieties and sweet toppings are what push it over.
What can change the impact?
  • Rolled vs. instant oats
  • Toppings (sugar, honey, dried fruit)
  • Portion size

GI values can vary with variety, ripeness, preparation and testing conditions. The value above is a typical published figure, not a universal prediction for every individual or every serving.

Frequently Asked Questions

What is the GI of Oatmeal (rolled oats, cooked)?

The typical published GI of Oatmeal (rolled oats, cooked) is 55, with a reported range of 55-83 (evidence level: Moderate).

How many carbohydrates are in Oatmeal (rolled oats, cooked)?

About 28.3 g per 1 cup cooked with water (234 g) (12.1 g per 100 g), including 4.0 g of fiber.

Is Oatmeal (rolled oats, cooked) suitable for people with diabetes?

Rolled oats in a normal serving are a moderate, fiber-carrying breakfast - the instant varieties and sweet toppings are what push it over.

What is the estimated glycemic load of Oatmeal (rolled oats, cooked)?

About 13.4 per 1 cup cooked with water (234 g), calculated as GI × available carbohydrate ÷ 100. See the methodology for the exact formula.

DMSafeHaven provides educational information based on publicly available nutrition databases and published research. It is not a substitute for individualized medical advice. Nutrition values: USDA FoodData Central (CC0). GI values: published tables (see methodology). GI/GL estimates do not predict any individual's glucose response — test your own blood glucose with your care team's guidance.