Certain foods can impede/block the absorption of  flavanols when combined with other foods high in flavanols. We also suspect the blending of these foods with a smoothie full of flavanols must make it more of a problem as well. One of the main worst foods per the research studies we can see is a banana (healthy carb option, along with honey). This means make sure to avoid consuming bananas, which are high in polyphenol oxidase that causes the blocking of the healthy flavanol nutrition, when having your Chocoberry smoothie or any nutrient berry, veggie, or nutrient dense smoothie/meal. Bananas are a really common smoothie ingredient so remember this fact to maximize your beverage and health. Here are also some top foods in flavanols you can pay attention to and scroll down to see the picture of other high polyphenol oxidase foods: In addition to banana, leaves of beetroot and pome fruits were the foods with the highest PPO activity, and all had the ability to use (−)-epicatechin as an enzyme substrate."

Resources:

https://medium.com/beingwell/smoothie-sabotage-skip-the-banana-7463d2e114c7

https://pubs.rsc.org/en/content/articlelanding/2023/FO/D3FO01599H

Article SUMMARY #1:

Impact of polyphenol oxidase on the bioavailability of flavan-3-ols in fruit smoothies: a controlled, single blinded, cross-over study†

Abstract

Flavan-3-ols are bioactive compounds found in a variety of fruits and vegetables (F&V) that have been linked to positive health benefits. Increasing habitual flavan-3-ol intake is challenged by the generally low consumption of F&V. While smoothies are a commonly endorsed, consumer-accepted means to increase the daily intake of these important foods, fruits used for smoothie preparation can have a high polyphenol oxidase (PPO) activity and thus potentially affect the content and bioavailability of flavan-3-ols. To assess whether or not consuming freshly prepared smoothies made with different PPO-containing fruit impacts the bioavailability of the flavan-3-ols, a controlled, single blinded and cross-over study was conducted in healthy men (n = 8) who consumed a flavan-3-ol-containing banana-based smoothie (high-PPO drink), a flavan-3-ol-containing mixed berry smoothie (low-PPO drink) and flavan-3-ols in a capsule format (control). The peak plasma concentration (Cmax) of flavan-3-ol metabolites after capsule intake was 680 ± 78 nmol L⁻¹, which was similar to the levels detected after the intake of the low PPO drink. In contrast, the intake of the high PPO drink resulted in a Cmax of 96 ± 47 nmol L⁻¹, 84% lower than that obtained after capsule intake. In a subsequent study (n = 11), flavan-3-ols were co-ingested with a high-PPO banana drink but contact prior to intake was prevented. In this context, plasma flavan-3-ol levels were still reduced, suggesting an effect possibly related to post-ingestion PPO activity degrading flavan-3-ols in the stomach. There was a substantial range in the PPO activity detected in 18 different fruits, vegetables and plant-derived dietary products. In conclusion, bioavailability of flavan-3-ols, and most likely other dietary polyphenol bioactives, can be reduced substantially by the co-ingestion of high PPO-containing products, the implications of which are of importance for dietary advice and food preparation both at home and in industrial settings.

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Article SUMMARY #2:

Smoothie Sabotage: Skip the Banana

YOU MIGHT WANT TO AVOID PUTTING that banana in your smoothie. Researchers recently discovered that adding a banana decreased health-promoting flavanol levels. Smoothie sabotage: Skip the banana.

Smoothies can be a convenient and tasty way for me to consume fruits and vegetables that promote health. I sometimes struggle to get in recommended quantities of fruits and vegetables, so smoothies have become appealing.

But what combination is optimal? Can I blend a banana and blueberry into a smoothie?

University of California, Davis researchers recently found that blending certain ingredients in smoothies can influence whether your body gets a nutritional boost. Smoothie sabotage.

Smoothies Are Popular

Smoothies have gained immense popularity recently as a convenient and nutritious way to consume fruits and vegetables.

Researchers valued the global smoothies market size at USD 6.68 billion in 2021. Rising awareness for a healthier life will likely boost market growth from 2023 to 2028.

The projected growth of healthy beverages will largely come from emerging economies such as China and India.

The drinks offer a quick and delicious means to pack vital nutrients into our diets, but one ingredient often finds its way into the blender without much thought: the banana.

While bananas are undeniably nutritious, their addition to every smoothie might only sometimes be the best choice for maximizing the nutritional benefits. Before we turn to smoothie sabotage, let’s look at the appeal of smoothies.

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