Banana

“That is it. And then I get in and every 20 minutes. Someone throws a banana over the boat and I eat it. Life is so good. So I do think sometimes for me, yeah, it's, it's really nice. And maybe, maybe, maybe for Hester as well in that she wakes up and just go, okay, he's still afloat.”

“It's like the universe letting you know you did it. You completed your journey. Fucking bananas, man. This is exactly it. But I love what you said there as well. I mean, certainly on the swim, it was so interesting. Sometimes I try to swim with gratitude as much as I can.”

“even help with exercise recovery. Then there's the banana smoothie question: why I think leaving ripe bananas out of a blueberry smoothie is a reasonable optimization. By the end of this episode, you'll know where the benefits look most credible, where the science is still preliminary, and how to build a simple blueberry habit without turning this useful food into a miracle cure.”

“I will also revisit the controversial blueberry and banana smoothie question: what the evidence really shows, where the uncertainty remains, and why I still take a cautious approach when trying to maximize blueberry polyphenol exposure.”

“Under certain conditions, it's actually kind of becoming this reaction chamber. And this is where bananas enter the story. Before we get into the banana-blueberry interaction, I want to be very clear. Bananas are a healthy food. A medium banana provides roughly three grams of fiber.”

“We all know that Americans fall short in the recommended fiber intake. So as a snack, a banana is a much, much better choice than any other ultra-processed food that comes in a package. But the question that I'm asking is actually much more narrow.”

“of an enzyme called polyphenol oxidase? Bananas have an enzyme in them called polyphenol oxidase. So what exactly is that enzyme? Polyphenol oxidase, or PPO for short, it's an enzyme that is found in many plant foods, including bananas, apples, potatoes, avocados, even berries.”

“So a banana turning brown is essentially that polyphenol oxidase chemistry that you can see. When the plant cells are disrupted, the polyphenol oxidase or the PPO becomes in contact.”

“So in one assay that was used by smoothie investigators, PPO activity was approximately 3,258 kilounits per 100 grams in banana compared with only 24 kilo units in avocado or 12 units in a high blueberry bush. So you're talking about 136 times more PPO activity in a banana compared to an avocado and about 270 times more activity than that found in a high blueberry bush blueberry.”

“And it's not that the bananas are unhealthy. It's that when a banana is blended with a polyphenol rich food like blueberries, it can bring a very large amount of enzymatic activity in direct contact with those compounds.”

“So banana polyphenol oxidase can directly oxidize polyphenols like epicatechin, catechin, and related what are called flavin-3-ols. Blueberries contain these compounds, although they are not the dominant polyphenols in blueberries.”

“The strongest human evidence for banana interaction does involve epicatechin, and we'll get into that later. But I do want to talk about the more consequential direct target for blueberries may actually be chlorogenic acid.”

“So the chlorogenic acid is often the most abundant non-anthocyanin polyphenol in blueberries. Banana PPO enzyme directly targets them. It directly oxidizes them. And when that happens, chlorogenic acid is converted into that highly reactive compound I referred to earlier called a quinone.”

“They have the strongest human evidence for many of the vascular benefits. So the argument that banana PPO enzyme only affects a relatively small amount of free epicatechin in blueberries is not accurate. It's incomplete. What we do know is that the banana PPO enzyme can directly oxidize epicatechin.”

“What we do not yet know is how much of that chemistry occurs in actual banana blueberry smoothie or how much it changes the physiological benefits of the blueberries themselves.”

“systems. But when we ask the human question, does consuming a high PPO food such as a banana actually reduce how much of a susceptible polyphenol reaches the circulation?”

“This study was published in 2023. Researchers blended about 177 grams of a ripe banana. It was a very large banana, and they blended it with almond milk. They compared the high PPO drink with a low PPO mixed berry smoothie, which had berries, blueberries, strawberries, blackberries, and raspberries.”

“So this is not a direct test of every polyphenol on blueberries. It was a very controlled test of what the banana PPO enzyme does to epicatechin. It is one polyphenol that is in blueberries in a small amount. And we do know that PPO directly oxidizes that polyphenol.”

“And we do know that PPO directly oxidizes that polyphenol. So the banana smoothie contained about 93 times more PPO activity than the mixed berry smoothie. That effect is very striking. After the banana smoothie, peak levels of epicatechin derived metabolites were 84% lower and total exposure over six hours was 81% lower”

“than the same compounds that were taken in the capsule without the banana smoothie. In contrast, the low PPO berry smoothie produced epicatechin levels similar to the capsule.”

“So in this part of the study, 11 men alternated sips between two drinks. The banana and the epicatechin were not actually mixed together beforehand, like in the previous study that they did. Even then, though, the blood levels of the epicatechin metabolites were 37% lower, which did suggest that the interaction continued after swallowing.”

“Then, the researchers went on to look at the mechanism, and I think that was also very convincing. So, in the blended banana drink, half of the epicatechin disappeared in less than 10 minutes at room temperature. When the researchers inhibited the PPO enzyme, that disappearance was prevented.”

“banana smoothie or whatever. It was the PPO enzyme that was driving that interaction. However, I do want to clarify the headline. This was not an 84% reduction in all blueberry polyphenols.”

“ultimately reaches the circulation. As I mentioned earlier, epicatechin is present in small amounts in blueberries, but epicatechin is not the only blueberry-relevant polyphenol that banana PPO can oxidize. As I also mentioned earlier, other studies done in blueberry models found that chlorogenic acid does interact and is”

“a direct target from PPO enzymes that are found in bananas, and the quinones that are formed from that reaction then degrade anthocyanins indirectly. That is why the broader blueberry question remains biologically plausible, even though it hasn't yet directly been tested in people.”

“And in that one human publication, a high PPO banana smoothie produced a very large reduction in circulating epicatechin derived metabolites from cocoa extract. So this was found in human circulation, right?”

“PPO enzyme was inhibited. What has not been measured is the complete blueberry question. We do not yet know how much blueberry chlorogenic acid or anthocyanin is altered when banana and blueberries are blended together. And no study has tested whether that interaction changes the vascular or the cognitive or the metabolic or the gut or the exercise-related benefits from blueberries.”

“a cup did not produce the same effect. So I'm not sure. That doesn't prove that adding banana removes enough polyphenols to eliminate the benefit, but it does tell us that you need an effective dose to have the health benefits. So when I make my blueberry smoothie, I am trying to maximize the polyphenols, and therefore I leave out the banana because it has high PPO activity.”

“I personally like that. It's not because I think bananas are unhealthy. It's just an optimization decision based on the chemistry we currently understand. I think someone else might reasonably decide they like the taste of the banana.”

“They like to add bananas to the blueberry smoothies and they're going to continue to do that. That's fine. I think the accurate message here is that banana PPO does reduce exposure to susceptible polyphenols like epicatechins. We also know that it oxidizes chlorogenic acid, which is high in blueberries, and that those quinones that are formed from the”

“yet been measured. So, where do I land on the banana question? I am not avoiding bananas. I'm choosing not to blend them with my blueberry smoothie. I'm deliberately trying to maximize for polyphenols. But the banana question really is only a small part of a much bigger story.”

“So you have to be a little bit careful there. There's some evidence that increasing dietary potassium, so eating potassium-rich foods, bananas, potatoes, things like that, and not doing this through supplements, by the way, because you can sort of get into a bit of trouble there, but can lower blood pressure based on the relationship that we see between potassium and analysterone in the kidney.”

“That's right. Because you break... You break the food down to tiny little particles, right? And your enzymes... Surface area, yeah. Right? Surface area to volume ratio. Your enzymes can break that food down. If you take a banana and you blend a banana, you get more energy from that banana than if you just eat the banana whole. People have done that experiment. Another example...”

“and funnily, spinach, are really bad. And at the top end, the bananas and the oranges and the melons are fine. So if you eat these damn things, they're designed to kill our cousins, the insects and the weeds.”

“It's, it's really reasonable. Of course we love to eat the rainbow. A banana is like 80 to a hundred grams, but I'll take like, you're a rutabaga person and you're going to do this all in rutabaga. That's still better than you not doing it in rutabaga. It's a, it's a good, this is how I like to think about nutrition as well as like, what do you need?”

“You're gonna be shocked and don't worry about the fruit. Everyone. You know, you're like, oh my gosh, these bananas are gonna kill me. They're not, you know, you're a, you're not eating the bananas, but you know, one of those loaves, I was just passing Starbucks, right? And one of those little piece of lemon loaves is like 430 calories.”

“Sugary fruits and vegetables or the starchy fruits and vegetables. So the tropical fruits we said, please be careful with like bananas, pineapples, mangoes, and then the starchy, if the vegetable grows in the ground, eat less of it relatively, but all other fruits and vegetables, and that's still a lot enjoy liberally and then prioritize protein and don't fear the fat that comes with that protein.”

“I do my strength training. I do not like to do fasted at all. I have to have like something like a banana. I have to have some glucose or something. So I'd love to get your take on training.”

“here, I would say our personal experience would match that some people are fine, some people are not. If you want to go just like practical recommendations, a banana and a protein shake, super easy. Yogurt, maybe in granola, we have a lot of our athletes that will train in the morning. That's a really common thing.”