21-05-2025
Bananas 101: Nutrition Facts and Health Benefits
Bananas are a source of fiber, potassium, vitamin B6, vitamin C, and various antioxidants and phytonutrients. Possible benefits include protecting against heart disease and supporting digestive health.
Bananas come from a family of plants called Musa that are native to Southeast Asia. They grow in many of the warmer areas of the world.
Many types and sizes exist. Their color usually ranges from green to yellow, but some varieties are red.
Read on to learn more about banana nutrition facts and possible health benefits.
Banana nutrition facts
The nutrition facts for 1 medium-sized banana, or a banana weighing 118 grams (g), include:
105 calories
88.4 g water
1.29 g protein
26.9 g carbohydrates
14.4 g sugars
3.07 g fiber
0.39 g fat
Carbs
Bananas are a rich source of carbs, which occur mainly as starch in unripe bananas and sugars in ripe bananas.
The carb composition of bananas changes drastically during ripening.
The main component of unripe bananas is starch. Green bananas contain around 70% starch measured in dry weight. This decreases with ripening.
The most common types of sugar in ripe bananas are sucrose, fructose, and glucose.
Bananas have a relatively low glycemic index (GI) of around 42 to 51, depending on their ripeness. The GI is a measure of how quickly carbs in food enter your bloodstream and raise blood sugar.
Fibers
A high proportion of the starch in unripe bananas is resistant starch, which passes through your gut undigested.
In your large intestine, this starch is fermented by bacteria to form butyrate, a short-chain fatty acid that appears to have beneficial effects on gut health.
Bananas are also a good source of other types of fiber, such as pectin. Some of the pectin in bananas is water-soluble.
When bananas ripen, the proportion of water-soluble pectin increases, which is one of the main reasons why bananas turn soft as they age.
Both pectin and resistant starch moderate the rise in blood sugar after a meal.
Vitamins and minerals in bananas
Bananas are a good source of several vitamins and minerals.
Potassium: Bananas are a good source of potassium. A diet high in potassium can lower blood pressure in people with elevated levels and benefits heart health.
Vitamin B6: Bananas are high in vitamin B6. One medium-sized banana contains around 0.433 milligrams (mg) of vitamin B6.
Vitamin C: Like most fruit, bananas are a good source of vitamin C. One medium-sized banana contains around 10.3 mg of vitamin C.
Health benefits of bananas
Bananas offer a number of possible health benefits.
Heart health
Bananas are high in potassium, a mineral that promotes heart health and normal blood pressure.
One medium-sized banana contains around 422 mg of potassium.
»Learn more: Heart-Healthy Foods
Digestive health
Unripe, green bananas contain considerable amounts of resistant starch and pectin, which are types of dietary fiber.
Resistant starch and pectins act as prebiotic nutrients, supporting the growth of beneficial gut bacteria.
In your gut, these fibers are fermented by beneficial bacteria that form butyrate, a short-chain fatty acid that promotes gut health.
Possible risks of bananas
There are mixed opinions on whether bananas are good for people with type 2 diabetes.
It's true that bananas are high in starch and sugar. One might expect them to cause a large rise in blood sugar.
But due to their low GI, moderate consumption of bananas should not raise blood sugar levels nearly as much as other high-carb foods.
That said, people with diabetes should avoid eating a lot of well-ripened bananas. It's always best to monitor blood sugar levels carefully after consuming high amounts of sugar and carbs.
Some people claim that bananas can cause constipation. However, bananas are high in soluble fiber, so they may actually help with constipation.
A banana allergy is also possible. Seek immediate medical help if you experience symptoms such as:
hives or an itchy rash
an itchy mouse or throat
angioedema, or swelling of the skin
»Learn more: Heart-Healthy Foods
The bottom line
Bananas are a good source of carbs and fibers. They contain decent amounts of several vitamins, minerals, and antioxidants. Potassium, vitamin C, catechin, and resistant starch are among their healthy nutrients.
Bananas may have numerous benefits, such as improved heart and digestive health.