Bananas could be ruining your smoothie’s health benefits

Researchers at UC Davis discovered that adding a banana to your smoothie may drastically reduce the absorption of flavanols — powerful compounds linked to heart and brain health. The culprit is polyphenol oxidase (PPO), an enzyme abundant in bananas that interferes with flavanol availability. In experiments, banana-based smoothies cut flavanol absorption by 84% compared to berry-based ones.