Popular smoothie ingredient may reduce one key health benefit, study suggests

Research suggests that bananas contain polyphenol oxidase (PPO), an enzyme capable of breaking down beneficial polyphenols found in ingredients like blueberries. A study published in Food & Function analyzing food absorption showed participants absorbed significantly fewer plant compounds after drinking a banana smoothie compared to taking supplements. However, some dietitians caution that the findings were based on only eight participants and that bananas still provide beneficial nutrients like fiber.