Banana: GI, GL, Carbs & Blood Sugar Impact
Glycemic index of banana (51), glycemic load, carbs per medium banana, ripeness effects, and whether people with diabetes can eat bananas.
Does Banana Raise Blood Sugar?
Yes — like any carbohydrate food — but how much depends on size and ripeness. A medium ripe banana carries about 27 g of carbohydrate and a GI of about 51. An under-ripe banana tests considerably lower, while a very ripe one tests higher.
How to Eat It
Choose a small or slightly green banana, and pair it with protein or nuts (Greek yogurt, peanut butter) to flatten the curve. Half a banana is a very manageable portion for many people.
Nutrition Facts (Banana)
| Nutrient | Per 100 g | Per serving |
|---|---|---|
| Calories | 89 kcal | 105 kcal |
| Carbohydrate | 22.8 g | 26.9 g |
| Fiber | 2.6 g | 3.1 g |
| Sugars | 12.2 g | 14.4 g |
| Protein | 1.1 g | 1.3 g |
| Fat | 0.3 g | 0.4 g |
Source: USDA FoodData Central (generic food item, per 100 g edible portion). Values may differ from brand-specific products.
Glycemic Index
Published GI: 51 (typical value).
Reported range: 30-62.
Evidence level: Moderate.
Note: Ripeness matters: an under-ripe banana tests much lower than an over-ripe one.
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 ≈ 12.2 per 1 medium banana (118 g).
Calculation: GI (51) × available carbohydrate per serving (23.8 g = 22.8 g − 2.6 g fiber) ÷ 100. Calculated by DMSafeHaven; formula per standard published GL methodology.
- Ripeness
- Size / portion
- Pairing with protein or nuts
- Fresh vs. dried
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.