Bananas Health Benefits, Vitamins, Iron, Calories, Major Nutrition Facts Everyone Should Know: A banana is a sweet, conveniently-packaged food when it comes to nutrition providing you with about 110 calories of high-fiber in each serving. A Banana is loaded with different vital minerals nutrients like calcium, iron, potassium, magnesium, manganese folate, niacin, and riboflavin but they also supply you with some of the vitamins contribute to the proper functioning of the body and keeping you healthy.