Should you avoid putting banana in a berry smoothie? UK surgeon debunks claim

According to Dr Rajan, the claim that bananas in berry smoothies lower the nutritional value is not scientific, and likely the result of bad communication.

There has been a claim circulating on social media that adding bananas to berry smoothies can destroy the berries' nutritional value. However, according to Dr Karan Rajan, a UK-based surgeon and health content creator, this is just an example of bad science communication.

There is no harm in adding bananas to a berry smoothie, shares Dr Rajan. (Unsplash)

Taking to Instagram on May 22, Dr Rajan explained where the claim originated and why it is okay to keep making smoothies with both berries and bananas.

Origin of the claim

The 2023 study, titled Impact of polyphenol oxidase on the bioavailability of flavan-3-ols in fruit smoothies: a controlled, single blinded, cross-over study, tested what happens when powdered flavonol from cocoa powder is added to two different smoothies, one containing banana and the other containing mixed berries, explained the surgeon.

The answer to the question of whether the enzyme polyphenol oxidase from a banana behaves the same way towards a dissolved cocoa powder extract as it does towards the flavonol packed in the food matrix of a berry remains unknown.

Why is it safe to add bananas to berry smoothies?

Berries contain a wide variety of polyphenols and other essential nutrients that offer multiple health benefits. As Dr Rajan expressed, “Even if the polyphenol oxidase enzyme from the bananas eliminated every single polyphenol in berries, which it does not, berries would still be amazing: fibre, folate, B vitamins, manganese, vitamin C.”

Dr Rajan further highlighted that the original study was conducted on a total of 19 people. While that does not prove the findings wrong in itself, it just raises questions on whether they can be generalised for a wider population.

“And the study just looked at one class of polyphenols, epicatechin. Berries contain dozens of structurally distinct polyphenol classes: anthocyanidins, procyanidins, quercetin, and ellagitannins. We have no data on what banana does to any of them,” shared Dr Rajan.

To summarise, he added, “Please keep enjoying bananas with your berry smoothies. Bad science communication is far more dangerous than any banana ever is. Keep blending away.”

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.

This report is based on user-generated content from social media. HT.com has not independently verified the claims and does not endorse them.