Fruit is great. 

It's tasty. 

It's full of fibre and packed with vitamins and minerals. 

And eating a diet that includes plenty of fruit is often considered necessary for optimal health. A fruit-rich diet may reduce the risk of chronic diseases (including strokes, heart disease and some cancers).

BUT... please remember that, as good as fruit is, it contains calories too. It is not a "free" food if you are trying to lose weight. Yes, you should be eating it but it must be accounted for in your overall calorie intake. 

If you are eating 4 bananas a day under the belief that they are a "free food" and you're not losing weight, it's probably because you are racking up nearly 500 additional calories.