Bananas are almost exclusively composed of water and carbs. The carb content of a standard banana size is 19 grams per medium banana and 27 grams per large banana.
A banana contains 2 - 4 grams of fiber, and its ripeness may affect its carb content.
The main nutrient in bananas is carbs, but the carb composition changes drastically during ripening. Yellow bananas contain less resistant starch than green bananas.
Resistant starch is an indigestible carbohydrate that escapes digestion and functions like fiber in the body.
It feeds friendly gut bacteria and is then transformed into short-chain fatty acids that provide calories later.
