Banana

Fruit · Musa spp.

What's inside banana, and where does it go in your body?

Mostly water and carbohydrate, with fiber, potassium and vitamin B6. Its starch turns to sugar as it ripens.

Inside 100 g

About 75 g water, 23 g carbohydrate (12 g of it sugars), 2.6 g fiber, 1.1 g protein, 0.3 g fat and 358 mg potassium. Roughly 89 kcal.

Peel vs edible

In USDA data the peel makes up roughly a third of a banana's weight. Nutrient values describe the edible flesh.

Ripening

Enzymes convert resistant starch into sugars as bananas ripen. Greener bananas have more resistant starch; riper ones taste sweeter.

Potassium in context

A banana is a good source, but potatoes, beans, lentils and spinach provide as much or more per serving.

Evidence & sources

• 100 g of raw banana provides about 358 mg potassium. Evidence: established. Known: Measured composition published in USDA FoodData Central. Unknown: Your banana's exact content varies with variety, size and ripeness. Source: USDA Agricultural Research Service, FoodData Central — Bananas, raw (SR Legacy) (April 2018).

Connected topics

• Potassium
• Fiber
• Carbohydrate
• Vitamin B6
• Vitamin C
• Magnesium
• Water
• Digestive System

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General education only, not medical advice. Drafted Oct 2026 · pending qualified expert review.