Why Leaders Should Skip the Banana in Their Morning Smoothie

Why Leaders Should Skip the Banana in Their Morning Smoothie / Alessandra Edwards

Life is busy, and for leaders, every decision counts, including what you put in your morning smoothie – bear with me…I’m heading somewhere with this.

Most of my executive clients, much like Barack Obama who famously streamlined his wardrobe to avoid decision fatigue, appreciate any hack that helps them conserve brain power by avoiding unnecessary choices.

The breakfast smoothie outshines many traditional breakfast options because it’s quick and easy to make, can be prepared in advance, is portable, and meets energy and protein needs in a delicious package.

However, recent findings suggest that one common ingredient—bananas—might be worth reconsidering.

Here’s why.

Polyphenol oxidase, the destroyer of goodness

Bananas contain a chemical called polyphenol oxidase (PPO). This enzyme has a knack for breaking down polyphenols, those beneficial molecules found in plants that are known for their cardiovascular and cognitive health benefits.

Polyphenols are abundant in blueberries, those little brain-boosting gems we love tossing into our smoothies. But here’s the scandal: when bananas and blueberries are blended together, the PPO in bananas starts degrading the valuable polyphenols from the blueberries. It’s like a messy divorce where the blueberries lose all their assets, leaving you without the cognitive perks you were hoping for.

Dr. Rhonda Fitzpatrick, a world-renowned biomedical scientist, explains that while bananas are nutritious and delicious, they might not be the best companion for your blueberries if you’re aiming to maximise brain health. 

So, maybe it’s time for bananas and blueberries to see other fruits!

This insight is backed by a study published in the Journal of the Royal Society of Chemistry last year. The study compared blood polyphenol levels in participants who consumed a smoothie with blueberry concentrate alone versus those who had a smoothie with both blueberry concentrate and banana.

The results were telling: participants who consumed the banana-blueberry combo had significantly lower polyphenol levels than those who skipped the banana.

Why does this matter for leaders?

Cognitive function is paramount. 

As a leader, your mental clarity, decision-making ability, and overall brain health are crucial. Polyphenols are celebrated for their role in enhancing cognitive function, protecting neurons, and reducing brain inflammation.

Ensuring that you get the maximum benefit from these compounds can give you a mental edge, helping you to think more clearly, make better decisions, and stay sharp throughout the day.

This isn’t to say that bananas are bad for you. They are rich in potassium, vitamins, and, when eaten unripe, prebiotic fibre, making them a healthy choice.

However, if your goal is to boost brain health with polyphenol-rich foods like blueberries, it’s wise to consume bananas separately. This simple adjustment can ensure that you’re not inadvertently sabotaging your smoothie’s potential cognitive benefits.


As leaders, it’s essential to stay informed and make choices that enhance our performance. Adjusting your smoothie ingredients might seem like a small change, but it can have a big impact on your cognitive health. So next time you’re blending up your morning drink, consider leaving out the banana and let your blueberries shine. Your brain will thank you for it.