For anyone trying to avoid food with high sugar content, green bananas are an option, whereas yellow bananas are not. Unripe bananas also have probiotic bacteria, a friendly bacterium that helps with good colon health. For anyone trying to avoid food with high sugar content, green bananas are an option, whereas yellow bananas are not. Drawbacks: Because antioxidant levels actually INCREASE as bananas age, unripe bananas are lower in this category. You could eat unripened bananas or ripened bananas and get the benefits of either one.