Bananas provide exceptional nutrition. They support muscles and nerves with potassium, help lower bad cholesterol with soluble fiber and, in addition to basic vitamins and minerals, they’re a great source of vitamin C. But there is more good news. Bananas contain prebiotics that support the good bacteria in your intestine, and in spite of their sweetness, they’re rated low on the glycemic index, so they only have a small to moderate impact on blood sugar. Bananas are an excellent source of dietary fiber. Just one banana contains 3.5 grams, which is 14 percent of the recommended daily value (based on a 2,000-calorie diet). For every 100 grams they weigh, bananas contain 1.8 grams of insoluble and 0.6 grams of soluble fiber.

Bananas are an exceptional source of vitamin B6 and vitamin C. They also provide folate, riboflavin, niacin and vitamin B5. You’ll receive smaller amounts of thiamin, vitamin A, vitamin E  and vitamin K.

Bananas are well known for providing 487 milligrams of potassium. This means that about 14 percent of the daily recommended value for potassium can be obtained by eating just one banana. They also supply 0.4 milligrams of manganese, 37 milligrams of magnesium  and between 1 to 3 percent DV of calcium, iron  and zinc.
Bananas contain a prebiotic called fructooligosaccharide (FOS). Prebiotics are natural substances found in many fruits and vegetables that nourish the good bacteria in the colon. FOS serves an important role because the good bacteria, such as Bifidobacterium bifidum and Lactobacillus acidophilus, help to strengthen the immune system, inhibit the growth of bad bacteria, increase the absorption of minerals such as calcium, and are being studied for a potential role in preventing some types of cancer.
If you’re allergic to latex, you may also be allergic to bananas. The American Academy of Family Physicians notes that the reasons are not well understood, but some foods cause an allergic reaction in people who are allergic to latex. The most common foods associated with a latex-related allergic reaction are bananas, avocados, chestnuts, kiwi fruit and passion fruit. 1% of the population is allergic to fruit or fruit juice.