What Is the Glycemic Load of a Banana? (And How to Lower It)
Quick answer: A medium ripe banana (about 120 g) has a Glycemic Index of ~51 and a Glycemic Load of roughly 13 — that’s in the “medium” range. An unripe green banana can be as low as 6. An overripe brown-spotted banana can climb to 16 or higher. Here’s what’s going on, and how to shift a banana into a lower-GL food in about ten seconds.
The math on a banana
Glycemic Load = GI × grams of carbohydrate in the serving ÷ 100. A medium banana weighs ~120 g and contains ~25 g of carbohydrate. Its GI is ~51. So GL = 51 × 25 ÷ 100 = 12.75, rounded to 13. That’s a medium GL — nowhere near the “sugar bomb” that keto content likes to claim, but not free, either.
Glycemic Load Calculator
Type any food, set the portion, and see its blood-sugar impact instantly.
Type a food and grams, then hit Calculate.
Why ripeness changes everything
A green banana stores most of its carbs as resistant starch — a fiber-like structure your small intestine can’t digest. As the banana ripens, enzymes convert that starch into free sugars (glucose, fructose, sucrose). The total carb count doesn’t change much; the form does. That’s why:
- Green (firm, no spots): GI ~30, GL ~6. Behaves almost like a low-carb food.
- Yellow (ripe, few spots): GI ~51, GL ~13. Medium.
- Brown-spotted (very ripe): GI ~60+, GL ~16+. Trending high.
How to lower the GL of a banana
Four practical moves, ranked by how much they help:
- Eat it less ripe. The single biggest lever. A firm, slightly-green banana can cut its blood-sugar impact in half compared to a spotted one.
- Pair it with protein or fat. A tablespoon of peanut butter (fat + protein), Greek yogurt, or a handful of almonds slows glucose absorption dramatically. Same carbs, flatter curve.
- Cut the portion. Half a banana halves the GL. Freeze the other half — great for smoothies.
- Add fiber. Chia seeds, ground flax, or a spoon of oat bran on top add soluble fiber that further blunts the spike.
Is a banana “bad” for fat loss?
No — but treating it like a free food is a mistake. A ripe banana delivers ~105 kcal and a medium GL. Two ripe bananas in a smoothie with fruit juice and honey pushes GL into “high” territory (25+) and delivers ~300 kcal that goes straight through the roof of your insulin response. One banana with protein at breakfast is fine. Two overripe bananas blended with juice is a dessert.
How a banana compares to other fruits
- Apple (120 g) — GL ~6. Lower.
- Orange (120 g) — GL ~5. Lower.
- Banana (120 g, ripe) — GL ~13. Medium.
- Pineapple (120 g) — GL ~7. Lower than banana.
- Mango (120 g) — GL ~9. Slightly lower.
- Dates, dried (60 g) — GL ~17. Much higher, even in a smaller serving.
See the full list on our GI/GL Database.
The pre-workout banana question
A ripe banana 20–30 minutes before training is one of the best-tolerated pre-workout carb sources on Earth: fast to digest, potassium-rich, easy on the stomach, and the medium GL means you’ll get useable energy without the crash mid-session. This is the one context where “the ripest banana wins.”
Bottom line
- Ripe medium banana ≈ GL 13 (medium).
- Ripeness matters more than any other single factor.
- Pair with fat or protein to blunt the spike.
- One banana per meal is fine for almost anyone chasing fat loss; two blended into a smoothie is not.
Want the GL of every other food you eat, without doing math? NutriGL Insight logs your meals and scores each one’s Glycemic Load automatically.
References
- Hermansen K et al. Postprandial glycaemic responses to banana ingested at various stages of ripeness. Eur J Clin Nutr.
- University of Sydney Glycemic Index Research Service, GI database (glycemicindex.com).
- Foster-Powell K et al. International table of GI & GL values: 2002. Am J Clin Nutr.