The Downside to Banana Smoothies for Polyphenol Absorption
An enzyme in bananas can destroy some of the phytonutrients in berries and cocoa, but there is a way to reduce the effect.
I did a Bananas in Smoothies ( ) live presentation with Q&A in November, if you want to check it out. Bottom line: Mixing bananas with certain healthy foods, like cocoa powder and possibly berries, may reduce some of their benefits.
For more on smoothies, check out the topic page ( ).
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Such a bummer. Presumably this applies to all polyphenols including that which you get in berries and purple sweet potatoes and even red cabbage, right?
The presumption is that it would apply: https://youtu.be/8grTXcdeZ-E?t=895
Sh*t…I love bananas 🍌
Aaaaarghhhh….. Don’t make me wait,,,,😜😜😜😜🍌🍌🍌Love your work guys 🇦🇺🦘👏👍😃
Would the same apply for apples?
Yes, but not as pronounced
@@xcast1 😟
And pears
ouch, that’s pretty bad, unfortunately there is no smoothy w/o banana!
maybe we’ll b save next video, oh, doc, please, save our Bananas!
damn it ! love bananas creamy additiong to my smoothies !… Super video ! cant wait for second part !
I did a Bananas in Smoothies live presentation with Q&A in November, if you want to check it out: https://www.youtube.com/watch?v=8grTXcdeZ-E&t=22s
I eat banana warmed up with oats in the microwave and then put berries on top does the banana in the oats warmed up in the microwave still have the negative effect on the berries??
If the banana gets hot enough, it should be fine: https://youtu.be/8grTXcdeZ-E?t=726
I would have thought that heating will only make this effect stronger, as warmer temps encourage banana to brown faster. Just a guess though!
@@Jack-tk3ub It sounded to me like you put on the berries after the banana has been heated. Then the enzyme is destroyed and can no longer degrade the berry polyphenols.
@@misterx3188 That sounds more accurate. I stand corrected
I have quit adding frozen bananas to my smoothies since DrGregor first came out with a video on this a year or so ago. I don’t miss the taste. I add some uncooked oatmeal for creaminess. My life is easier not dealing with bananas, less fruit flies too.
True….I still think bananas are healthy for us though. After hearing about this I will on occasion make a banana smoothie with walnuts, oatmeal and cinnamon and clove……sprinkle in some wheat germ and ground flax seed for added measure along with a little honey for an extra added sweet kick to it and BOOM! ……..I’ll make my berry smoothies without the bananas now and the chocolate ones I use mangos instead, it’s not bad……anyway, I just hope people don’t shy away from eating bananas because of this discovery as I believe they are good for you ….
What about cooked bananas with oatmeal?
That should be fine: https://youtu.be/8grTXcdeZ-E?t=726
Heat deactivates the enzyme
Cooking should denature any banana enzymes.
How about adding some tofu? Might be better than protein powder for the vegans.
Silken tofu could work but the taste is more pasty/beany than creamy/sweet with bananas. I’m not a bodybuilder though so I’m not at all concerned with my protein intake.
So does that mean that I need to _double the amount of cocoa_ I add to my banana based smoothies? My mouth waters at the thought.
Okay we’ve already heard this story, but what if you freeze the bananas? Or what if you add citrus to it like you would to prevent an avocado from browning? For example, I used to make kale smoothies and I would add pineapple, sunflower seeds, etc adding banana last and pouring orange juice on the banana. It seems like this could deactivate the polyphenol oxidase or reduce it dramatically from doing its thing. So is that a way to deactivate the enzyme or is freezing perhaps???????
Here’s what I found:
“To destroy the enzyme polyphenol oxidase (PPO), you can use methods that involve heat, acidity, or cold, as the enzyme is sensitive to these conditions:
1. Heat (Blanching or Cooking): PPO is heat-sensitive, so exposing fruits like blueberries to high temperatures will denature the enzyme, stopping the browning process. Blanching involves briefly boiling the fruit and then cooling it rapidly in ice water.
2. Acidic Environments: PPO activity can be inhibited by lowering the pH. Adding lemon juice or another acidic substance to the fruit can slow or stop the browning by inactivating the enzyme.
3. Cold (Freezing): Freezing can also halt PPO activity. However, while freezing prevents the enzyme from functioning, it doesn’t permanently destroy PPO, so when the fruit thaws, some enzymatic activity could resume unless other factors like heat or acidity are used.
Each method depends on your needs, whether you’re preserving the fruit for cooking or storage.”
So are bananas ruining my cacao, yogurt, kefir, kale ginger, berries and pineapple smoothies? Or is just the longer a smoothie is mixed with a banana before drank, the longer it affects this specific nutrional absorption because the banana absorbed…so where would it go? Ive always known not to let most smoothies sit between 2-4 hours after making them. This added onto that belief.
I mean based on what he said, even if you drink it immediately, it might reduce the polyphenols by 37%. If you let it wait for 10 mins before drinking it might reduce it up to 50%
I love this channel!
What can we use instead?
Mangoes
I feel better about just munching on whole fruit and nuts while sipping coffee for the past decade.
biggest cliffhanger in history 🙁
I have a question: He said: “Okay, no problem, we can just not eat brown bananas, as that’s visual evidence that many of the polyphenols have been lost.” So what does that mean? If I buy bananas and they don’t get eaten right away, I freeze them and then use them for nice cream or banana bread etc. Does this mean that there is really very little nutritional value to the bananas in that state? Do I want to start freezing bananas before they brown?
Damn! A lot of cliff hangers these days.