To Get More Flavanols in Your Smoothie, Skip Banana?

"We were really surprised to see how quickly adding a single banana decreased the level of flavanols in the smoothie and the levels of flavanol absorbed in the body," Javier Ottaviani says. Indi Photostudio/Shutterstock

Certain combinations of ingredients can reduce the amount of flavanols in a smoothie, a study shows.

The study, published in the journal Food and Function, used smoothies to test how various levels of polyphenol oxidase (PPO), an enzyme in many fruits and vegetables, affect the levels of flavonols in food that the body absorbs. Flavanols are a group of bioactive compounds that are good for your heart and cognitive health and are naturally found in apples, pears, blueberries, blackberries, grapes, and cocoa—common smoothie ingredients.