The hour is serious for all lovers of smoothies. Without knowing it, they partially lose the benefits of their favorite mixtures by adding… a banana. This is revealed by an American study published in the journal Food.
Quick reminder: the smoothie is a smooth preparation made from apples, bananas, blueberries, avocado, etc. mixed with possibly milk or yoghurt, crushed ice, according to individual tastes. It is therefore a simple and effective way to reach the famous nutritional recommendations which recommend five fruits and vegetables per day. Some of these foods, such as apples, pears, blueberries, peaches, grapes and cocoa, are naturally rich in flavonols, compounds whose consumption improves cardiovascular and cognitive health, including memory. Hence the importance of choosing the ingredients of your smoothie carefully.
This is where the banana causes trouble. It is rich in polyphenol oxidases, enzymes that break down flavonols. In the study conducted by the University of California, the researchers showed how this enzymatic activity could be fatal to the smoothie. They formed two test groups. In the first, the participants swallowed a banana-based smoothie, while in the second, the preparation contained mainly berries, therefore low in enzymes. Both groups also ingested a capsule of flavanols so that everyone started the experience with the same amount of the precious substance. The scientists then measured flavanol levels in blood and urine.
The results were impressive. Those who drank the banana smoothie, which is therefore rich in polyphenol oxidases, had on average 84% less flavanols. The banana enzymes had wiped out the expected heart and memory benefits.
The researchers therefore recommend not to mix the banana with foods rich in flavanols, such as apple, berries, cocoa. This does not mean that you should deprive yourself of bananas, because according to Professor Boris Hansel it is an excellent fruit for “food balance and does not particularly gain weight!” »
