In reality, bananas are extremely healthy and rich in nutrients. Bananas have a glycaemic index of approximately 51, which is extremely low on the glycaemic index! This fruit is high in mineral content as it is one of the richest sources of potassium that is essential to maintain good blood pressure, and helps maintain optimal muscle contraction. That's the reason sports persons are often seen having a banana during a sport to give them energy and potassium. They also help to reduce depression due to the presence of tryptophan, a well-known mood enhancer. A good source of fibre, they also help to relieve constipation.