Bananas in Smoothies: Yes or No? (Presentation)

hello everyone hopefully third time is the charm first time I got Co we were trying to do this H banana smoothies thing and then just today tried to do it as part of a live Q&A and technologically it all failed so although unfortunately this won't be live won't be able to take questions but I will get this information out there um and so hopefully this will work fingers crossed all right okay well so the first part of this will sound familiar who were watching on YouTube or Facebook until it all collapsed but now you'll actually be able to see the PDFs hopefully actually see the studies that I'm talking about okay we all know there are recommended daily intakes of essential nutrients like vitamins to prevent deficiencies but recently hopefully you can see that but recently the first dietary recommendation for a bioactive food compound was published bioactive food compounds as you can see in green here um are not necessary for basic human needs but may have health benefits for example these PL metabolites here in red known as flavonoids flavonoids are a type of polyphenol which are uh which of which the most commonly consumed one is these flaven thols also known as just flavanols a review of the literature here up in blue um suggests that intake of 400 to 600 milligrams a day of these flavonol would be beneficial for cardiovascular protection such as here in red uh potential for improving blood pressure cholesterol blood sugars right and now note here in Gray um that this is specifically a food guideline not a supplement guideline though really it's actually more like a beverage guideline since if you look at the uh zoom out a little bit there um uh if you look at the primary sources it's really tea green or black is the easiest way to reach those levels though there certainly some in a variety of berries and cocoa however done there's an enzyme called polyphenol oxidase that can break down these wonderful polyphenols like flavonoids that is what makes certain fruits and vegetables as you can see here in in green brown when you cut them uh such as bananas and potatoes now why would a plant do that to it itself well apparently it is um a defense mechanism um it's part of the plants immune system as you can see there in Orange um and uh when exposed to oxygen um what happens is that polyphenol oxidates can oxidize polyphenols into these breakdown products which have antimicrobial activity so when a banana gets bruised for example uh they're in Gray you cut or you cut open avocado or something the polyphenol oxidases can start oxidizing polyphenols into these defensive compounds that can glom together here in red um forming a dark compound called melanin same class of compounds that darkens the skin of banana also darkens our skin too okay so no problem we can just not eat bananas that have turned brown right because that's Visual Evidence that many of the polyphenols have been lost ah but what if you mix that banana which you know is filled with that polyphenol oxidase enzyme in a smoothie with polyphenol rich foods like berries or cocoa might that might that end why you end up with less nutrition well big chocolate funded researchers sought to find out and so what they did is they put a about a half cup of Coco worth of cocoa flavanol into in a banana containing smoothie compared to the same amount in a berry smoothie with no banana so here is a measure okay so here um is a measure of how many cocoa flavanol make it into your bloodstream um within hours 1 two 3 three four five six hours after eating uh the chocy berry smoothie compared to the same amount of cocoa blended into a banana smoothie right so the same amount of those cocoa goodies but it's almost as if there was no cocoa in there at all presumably because the banana enzymes chopped up all the chocolate goodies um let's not presume though um they Blended up that uh chocolatey banana smoothie again um which was just banana almond milk cocoa flavanol and then they just measured the level of flavanol as the Smoothie sat for an hour check it out that is what happened the cocoa flavanol plumed more than 90% a halflife of about about 10 10 minutes um uh so uh so every 10 minutes the levels of polyphenols drop in half now how do we know it was for sure it was this polyphenol oxidase enzyme because then if you add um various polyphenol Inhibitors um then uh what um then uh then they block the effect okay so no problem if you add bananas to your smoothies just you have to chug them down before the enzyme does its job right I mean presumably the enzyme would be deactivated when it hit the Acid Bath of our stomach but you don't know until you put it to the test and I love that the research did all this all these extra steps here uh so here you are in in in green here what they did is this time they had study participants um alternate sips alternate sips U between a straight banana almond milk smoothie um and like chocolate milk chocolate flavonoids plus the almond milk right so there was no premixing uh in the blender between the banana enzyme and the flavanol just mixing in the stomach such such kind of an elegant research move Okay so here's how many cocoa flavanols here we go here's how many cocoa flavonol make it in your bloodstream um uh sipping the uh chocolate milk Alone um here with these kind of brown greenish Brown uh uh uh little um data here um and then here is when it's mixing just in the stomach when you're alternating SS with the banana smoothie um and so uh that you get 37% Less in your bloodstream showing that the banana enzyme can still do some polyphenol damage in your stomach um it's starting to get dark and so my screen's GNA start to yellow because I cut out that the blue blocker um a Blue Block effect but I just turned that off so we should be good okay um and indeed um in a simulated stomach acid um in a in kind of simulated stomach acid conditions um yes the polyphenol oxidase um is indeed down but not out okay so yeah um if you drink some smoothie with a banana and it's better not to let it sit around but even if you drink it immediately you can get less polyphenols in your system than if you had have skipped the banana all right all right but bananas make smoothies so rich and creamy I mean anything we can add to the Smoothie to counter the banana enzymes effects that's exactly what I'll cover next but not really next because that's what I would have said in the video but we're all gonna be covering right here right now um actually it's uh let me turn down that light a little bit um oh it's not showing up all right it's okay it's okay all right um let me just take a few seconds though uh before I continue um with this story to ask for your help um we usually made this a YouTube fundraiser but now it's not really on YouTube but um if you're watching this on nutritionfacts.org um uh and you find this valuable please consider making a tax deductible donation to support this wonderful work um uh and uh and uh so as a kind of end of year show of thanks uh we you know we don't accept money from food companies or supplement companies or you know kitchen Gizmo companies or anything like that just individual donors like you so thank you so much for your support okay back to our regularly scheduled program there's one food that has even more polyphenol ox activities in banana and it's a vegetable that's not a potato what vegetable turns brown that's not a white potato all right let's go look uh okay 20 um let's find out aha here we go so here's polyphenol polyphenol oxidase activity in various fruits and vegetables and oh oh white mushrooms white button mushrooms as you can see have more polyphenol uh um um oxid activity than even bananas now for those of you thinking uh don't worry I don't think I'm expect to be adding any mushrooms into my smoothies anytime soon now some people do add avocados um to smoothies um or make like a chocolate avocado pudding and here's the question what if you eat mushrooms with a meal packed with polyphenol rich foods right might it mix in your stomach and decrease the absorption like the an thein in red cabbage or berries for dessert right um and look you could also be having some potatoes with your meal or eggplant um with your meal which also as you can see contains it um now note though however this is is for fresh produce right so you know we're not worrying about the eggplant potatoes um and uh the enzyme is utterly destroyed by cooking so this is a inactivation of the mushroom uh polyphenol oxidates inam and as you can see um it plummets readily um and look remember we should be cooking our mushrooms anyway right because of the gutin most of our mushrooms uh you don't have to cook oyster mushrooms but the white and criminy and portella mushrooms right so problem solved right they uh you know so you don't have to worry about cooked potatoes cooked eggplant cooked mushrooms okay uh but who wants to cook their bananas though right what else could we put in a smoothie instead my personal favorite is mango which you buy Frozen when it's not in season uh do we have to worry about that having a polyphenol eating enzyme s well what happens when you cut open a mango does it go Brown no it doesn't go Brown which should show you um exactly um what this data uh shows here and that is uh if you look um that um mango right here has oh maybe 500 times less than that banana this is polyphenol o um in activity this is the activity of that enzyme that destroys polyphenols like flavonoids right now the Apple certainly doesn't um uh doesn't surprise me right because what what happens with apples turns brown but what is with this be greens I did not know about that so if you're making a green smoothie better use something like kale which has enzyme levels so low they're below the level of detection okay uh but boy the Smoothie study raises so many interesting questions right so uh what forget smoothies should you not add bananas to your oatmeal right because the bananas in your stomach would mix with like the berries or the cocoa that you put in your oatmeal um and indeed um that is what we should expect so I no longer add bananas to my cran chocolate pomegranate breakfast bowl um that was one of my cooking videos if you missed it um uh and uh since you know I don't want to lose any of those polyphenols there's so many wonderful ingredients in that I don't want to lose any don't want any of those destroyed that 37% decrease in your stomach um when it all mixes with that enzyme okay but what if you're not making something chocolaty the um this study W only tested the effects of the enzyme on Coco flavonol like they didn't check to see if like mixing bananas with berries would affect the berry phytonutrients but the presumption is that it would um and so H what does that mean for like ready to drink bottled smoothie drinks that you might find in the store right that may be sitting on the shelf well if it's been pasteurized then it should be okay right because the heat destroys that enzyme uh that's vegetables are blanched you know before they're frozen to destroy the enzymes even just heating uh bananas to 70 let me see table two that's figure two I'm looking for oh yeah yeah yeah yeah uh okay um so here we're in this is inactivation methods for that enzyme of bananas even just heating um in here we're looking at the T2 data right here um even just heating banana to like 70 degrees C which is like hot tea 70 degrees CSUS for two minutes in the presence of vitamin C and citric acid which might come from lemon juice for example would suppress the enzyme by 80% I'm not suggesting drinking hot smoothies but rather that those pasteurized smoothie drinks depending on the ingredients may not have the same problem as fresh made smoothies uh what about just the adding the vitamin C and citric acid alone like putting lemon juice in your smoothie that is the T1 oh here let me move this over that's the T1 data here um and as you can see it only Cuts enzy activity by about 133% without the heating step however it does work wonders for apples so um as you can see here um a a cut Apple um you just add some lemon juice and you can cut that activity nearly in half um explaining why adding lemon juice to your fruit salad you know keeps the apples and your fruit salad from turning brown okay anything we can add to a banana smoothie to inhibit the enzyme so we can still use bananas but somehow block the enzyme well they Ed to put um blue there we go they use to put sulfites in fresh fruits and vegetables to block that enzyme until they were banned in 1986 following cases of sulfite induced asthma they are still used in dried fruit though to prevent Browning the apricots on the left um are sulfured with sulfites and the ones on the right are not um it's purely cosmetic you want to get the unsulfured so you don't have to worry about um sulfite induced respiratory problems what um so okay sulfites are kind of OD off the table um but what about other what about natural agents what can we do for natural anti-browning agents to block this puppy well as you can see in Orange there onion extracts can prevent the Browning of of uh of pears uh and you see in in Gray both fresh and cooked onion juice um both work but there has got to be something better for your smoothies and indeed pineapple juice as you can see in in purple there does seem to help keep apples from browning um and bananas too uh for that matter but that was after soaking in pineapple juice for three days so it's not clear if it would work right away um there was a study um here underlined in yellow um comparing lemon juice and white wine to prevent Browning in pastry dough uh you've heard of hard cider hard Seltzer well the lemon juice it appears um beat out the wine so uh better a Lemon Squeeze than drinking a hard smoothie anyway okay so that's the let me stop sharing here that's the story on bananas and smooth so should you not eat bananas no you can eat bananas anytime you just don't want to eat bananas you just want to have the bananas in your stomach at the same time you have other healthy foods like berries cocoa tea um and so but like as a snack on its own totally fine uh but uh smooth the aside still um you could uh you could impair some of the um uh you could destroy some of the phytonutrients if you had it in your stomach at the same time as meal and same thing with uh you know uh uncooked mushrooms and some of those other things oh like the the the avocado um anyway I'm sure this raised a lots of questions and I was hoping to take lots of questions today that was before the the tech disaster but uh certainly be happy to answer next time I do Q&A thank you so much everyone thank you for everyone who decided to support us this year um this will actually this topic will actually be up in actual video on nutritionfacts.org all polished and fancy um but didn't want to wait for you to get this important information have a good night

Channel: NutritionFacts.org

Views: 147,764

Keywords: green smoothie, healthy smoothies, fruit smoothie, bananas in smoothies, dr greger, nutritionfacts.org, daily dozen dr greger, banana in smoothie bad, polyphenol oxidase, banana polyphenol oxidase, banana berry smoothie

Id: 8grTXcdeZ-E

Length: 20min 32sec (1232 seconds)

Published: Mon Nov 20 2023