What Do Bananas Have In Them Nutrition Facts?

Bananas are one of the most widely eaten fruits in the United States, and their nutrition is fairly simple to describe. A medium banana has about 105 calories, 27 grams of carbohydrate, 3 grams of fiber, and roughly 422 milligrams of potassium. It also provides vitamin B6, vitamin C, and magnesium, with almost no fat and about 1 gram of protein.

Those numbers come from standard USDA nutrient data for a banana about 7 to 8 inches long. The exact amounts shift with size and ripeness, but the broad picture stays the same. Bananas are a carbohydrate-rich fruit with meaningful potassium and vitamin B6, and very little fat or protein.

What Do Bananas Have In Them Nutrition Facts?

A medium banana delivers a compact package of carbohydrate, fiber, vitamins, and minerals in a fruit you can eat without any preparation.

Here is how the main nutrients break down for one medium banana, based on USDA data:

That vitamin B6 figure covers a large share of what most adults need in a day. Potassium at 422 milligrams is also substantial, though it sits well below the daily target most adults are advised to reach. Bananas are not a concentrated source of any single nutrient the way, say, an orange is for vitamin C. Their value comes from the combination.

One point worth knowing: bananas contain almost no fat and very little protein. If you are building a meal around them, they work as a carbohydrate source, not as a protein source.

How Many Calories Are in a Banana?

Calories track closely with size, and banana sizes vary more than most people expect.

• A small banana, about 6 to 7 inches, has roughly 90 calories.
• A medium banana, about 7 to 8 inches, has about 105 calories.
• A large banana, about 8 to 9 inches, has roughly 121 calories.

The difference between a small and a large banana is about 30 calories, which is modest. Where calories add up is in how bananas are eaten. A plain banana and a banana blended into a shake with peanut butter, honey, and whole milk are not the same thing nutritionally. The fruit is not the variable there.

For most people, the calorie content of a banana is not a reason to avoid it. It is a filling fruit with fiber, and the fiber slows how quickly the sugar enters the bloodstream compared with something like juice.

Does a Banana Have More Sugar Than Other Fruit?

A medium banana has about 14 grams of sugar, which is on the higher end among common fruits, but the comparison is more nuanced than the number suggests.

An apple of similar size has around 19 grams of sugar. A cup of grapes has about 23 grams. So bananas are not unusually high in sugar among fruits. What bananas do have is a starch content that changes as they ripen, and that change affects both taste and how the body handles them.

An unripe green banana is high in resistant starch, a type of carbohydrate the small intestine does not fully digest. As the banana ripens and turns yellow, enzymes convert that starch into sugars, mostly glucose, fructose, and sucrose. A heavily spotted banana is sweeter because more of its starch has become sugar.

This matters for two reasons. First, riper bananas taste sweeter and have a slightly higher glycemic impact. Second, the resistant starch in less ripe bananas acts more like fiber, feeding gut bacteria rather than raising blood sugar. Neither version is “bad.” They are simply different stages of the same fruit.

The sugar in a whole banana comes packaged with fiber and potassium, which is not true of added sugar in processed foods. That distinction is real, even if the gram count looks similar on a label.

What Vitamins and Minerals Are in Bananas?

Bananas are best known for potassium, but vitamin B6 is where they make their strongest nutritional contribution relative to daily needs.

A medium banana provides about 0.4 milligrams of vitamin B6. For most adults, that is roughly a quarter to a third of the daily requirement, depending on age and sex. Vitamin B6 is involved in over 100 enzyme reactions, many related to protein metabolism and the production of neurotransmitters.

Potassium at 422 milligrams supports normal muscle function, nerve signaling, and blood pressure regulation. The relationship between potassium and blood pressure is well established. Diets higher in potassium tend to be associated with lower blood pressure, and federal dietary guidance encourages adults to increase potassium intake from food. Most Americans fall short of the recommended potassium intake, so a banana contributes meaningfully even though it does not close the gap on its own.

Bananas also supply vitamin C and magnesium in smaller amounts. Vitamin C at about 10 milligrams is a modest contribution compared with citrus or bell peppers. Magnesium at roughly 32 milligrams is a smaller fraction of daily needs but still useful.

One caveat worth stating plainly: people with advanced kidney disease are often advised to limit potassium. If you have kidney disease, talk to your doctor before increasing potassium-rich foods like bananas. That guidance is standard clinical practice and not something to work out on your own.

Are Bananas Good for Digestion and Gut Health?

Bananas contain fiber and, when less ripe, resistant starch, both of which interact with the digestive system in ways that are reasonably well understood.

The 3 grams of fiber in a medium banana is a moderate amount. Fiber adds bulk to stool and can help with regularity, though bananas are not a high-fiber food compared with beans, lentils, or whole grains. The resistant starch in less ripe bananas ferments in the colon, where gut bacteria break it down. This fermentation produces short-chain fatty acids, which are thought to support the cells lining the colon.

There is a common belief that bananas help with diarrhea and constipation at the same time. The evidence here is not strong for either claim. Some clinicians suggest bananas as part of a bland diet during recovery from diarrhea, largely because they are easy to tolerate and replace some potassium. That is common practice more than a well-supported treatment.

For constipation, bananas are sometimes recommended, but the evidence is mixed, and unripe bananas may actually worsen it in some people. If you are relying on bananas alone to fix a digestive problem, they are unlikely to be enough.

Do Bananas Help With Blood Pressure or Muscle Cramps?

Potassium is involved in both blood pressure regulation and muscle function, but the evidence for bananas specifically is uneven across these two claims.

For blood pressure, the broader evidence on potassium is solid. Diets rich in potassium are associated with lower blood pressure, and this is reflected in dietary guidelines that encourage higher potassium intake. A banana contributes to that intake, but no study has shown that eating bananas alone lowers blood pressure in a meaningful way. The effect comes from overall diet, not one fruit.

For muscle cramps, the picture is weaker. The idea that low potassium causes cramps is widespread, but research has not consistently supported it. Some studies suggest cramps are more related to fatigue and nerve function than to electrolyte depletion in most healthy people. Eating a banana after exercise is fine, but it is not a proven fix for cramping.

Where bananas do help is post-exercise carbohydrate replacement. They provide quick carbohydrate and some potassium, which is why they show up at races and gyms. That role is reasonable, though a banana is not a superior recovery food compared with other carbohydrate sources.

Are Bananas Healthy for Everyone?

For most people, bananas are a nutritious, affordable, and convenient fruit with no meaningful downside.

There are a few groups who should pay attention. People with advanced kidney disease may need to limit potassium and should follow their doctor’s guidance. People with a banana allergy, which is uncommon but real and sometimes linked to latex allergy, should avoid them. And people managing blood sugar should know that riper bananas raise blood sugar somewhat faster than less ripe ones, though a whole banana’s fiber blunts that effect compared with juice or candy.

For everyone else, the question is not whether bananas are healthy. It is whether they fit into an overall diet that includes a range of fruits, vegetables, and whole foods. A banana is a good food. It is not a cure for anything, and no single fruit is.