An apple a day is said to keep the doctor away, but what about a banana?

Bananas are a great source of fiber, potassium, vitamin C and other antioxidants and phytonutrients, according to Healthline. Approximately 96% of American households buy bananas at least once a month, the Farmer's Almanac reports.

It is recommended that adults eat around 1.5 to 2 cups of fruit per day, according to the Centers for Disease Control and Prevention. If you're looking to increase your intake, here are some nutritional facts about the "a-peeling" fruit: bananas.

How many calories are in a banana? 

A medium-sized banana is around 105 calories, according to the U.S. Department of Agriculture.  

How many carbs are in a banana?

A medium banana contains approximately 27 grams of carbohydrates.

How much potassium is in a banana?

A medium banana contains 422 milligrams of potassium. 

What are the healthiest fruits?This one has cognitive and cardiovascular benefits.

How much sugar is in a banana?

A medium banana contains about 14.4 grams of total sugars. 

Banana nutrition facts

According to the USDA, a medium banana has:

• 105 calories
• 1.29 grams of protein
• 0.389 grams of total fat
• 26.9 grams of carbohydrates
• 3.07 grams of fiber
• 422 milligrams of potassium
• 10.3 milligrams of vitamin C
• 0.433 milligrams of vitamin B-6
• 5.9 milligrams of calcium

How to ripen a banana 

There are many ways to ripen a banana. While some methods bring quicker results, all can help turn the fruit yellow. 

Bananas ripen naturally and release ethylene gas, or the “fruit-ripening hormone,” according to Frontiers for Young Minds. Oxygen also aids in the fruit-ripening process – the less oxygen a fruit gets, the slower it will ripen. 

If you're not in a rush, keep your bananas in a bunch and let them ripen at their own pace. Green bananas usually take three to five days to become yellow and ready to eat or cook with, Bon Appétit reports.

However, if you need ripe bananas fast, there are a few ways to do so.

Your oven can help ripen bananas, according to Southern Living. Preheat your oven to 300 degrees Fahrenheit and place unpeeled bananas on a parchment-lined baking sheet. Bake the bananas until the skin turns black and the fruit is soft (for about 20 minutes). Allow the bananas to cool and they'll be ready to use. This method works best if you're using bananas to cook with, such as baking muffins or banana bread.

Another technique to speed up a banana's ripening is to place it in a paper bag with another ethylene-producing fruit. This could be an apple or avocado. The ethylene gas from the other fruit will help the banana ripen faster, according to Frontiers for Young Minds. Make sure the bag is tightly sealed. The bananas should be ready in the next day or two.

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