Base Knowledge: Polyphenols
Can fruit help you recover from a workout? The science behind "eating the rainbow."
The Upshot, Upfront:
Polyphenols are a type of nutrient from plants shown to have antioxidant and anti-inflammatory properties.
They probably help with post-workout muscle damage.
It’s easy to get most athletes to eat fruit. It provides sugar for fuel, it’s hydrating, and it’s a tasty, natural alternative to bars and gels. Not that bars and gels are bad—but when training or competing for two+ hours and subsisting mainly on consumer packaged goods, it’s nice to mix it up by putting something real in your mouth.
Although we tend not to think about it as much, fruit is also packed with vitamins, minerals, and polyphenols.
If I lost you at polyphenols, don’t worry about it. Odds are that you’ve heard about these powerful antioxidants, even if not by that name. Better known polyphenols include quercetin and resveratrol, the substance in wine made trendy by The French Paradox (although you can also get it from grapes). Polyphenols are the heart-healthy factor that gives chocolate its sometime abused health halo. (A square of dark chocolate may have cardiovascular benefits, but an entire bag of milk chocolate Hersey’s Kisses? Not so much.)
Bacchanalian indulgences aside, polyphenols are the main reason we’re urged to “eat a rainbow of fruits and veggies.” Although they aren’t considered essential nutrients and the FDA hasn’t assigned a Daily Value for any of them, science keeps finding more and more reasons why they’re important to our health.
For our purposes, sports nutrition research suggests the antioxidant and anti-inflammatory properties in polyphenols play a big role in post-exercise and maybe even during-exercise performance.
So break away from the pack by making them your semi-secret recovery weapon.
Phytonutrients for the win!
Polyphenols are a type of phytonutrient—compounds unique to plants that protect them from UV rays, promote pollination, and fight off pests, among other things. Some phytonutrients also give fruits and vegetables their distinct colors and flavors.
For example, blueberries stain your shirt blue courtesy of a polyphenol called anthocyanin. It’s also a big reason why blueberries have been shown to have cardiovascular and neuroprotective benefits.
From an evolutionary perspective, phytonutrients are a trip. Polyphenols in particular seem to prove healthful to who or whatever eats them. This is not coincidence. Their bright colors and pleasant flavors entice animals to eat the fruit they reside in. Most animals aren’t very discerning about what part of a fruit they eat, so they gobble down the whole thing, including seeds—which make their way through the digestive system and out the backend swaddled in a beautiful blop of fertilizer. These seeds grow into new trees or vines or whatever. They bear fruit—and the cycle begins anew.
Meanwhile, thanks to the health benefits, fruit-eating animals probably outlive non-fruit eaters. These animals prosper as they eat more fruit and poop more seeds. Darwin meets Disney as the Circle of Life propagates all species concerned.
A taxing lesson in plant nutrient taxonomy.
Polyphenols are simple to grasp. They are colorful substances unique to plants that have stress- and inflammation-fighting effects on humans. Unfortunately, science works hard to stifle this simplicity by giving them the world’s most convoluted naming system. The lineage in Lord of the Rings is less confusing than the taxonomy for phytonutrients.
There are thousands of phytonutrients—more than 10,000 by one count. They’re placed into a massive org chart that goes several layers deep. Many of them go by multiple names, often quite similar. And different authorities organize the system in different ways. If you’re a layman science nerd, this makes understanding research papers about phytonutrients pretty rough. And the popular media often flat-out gets them wrong.
Here’s a breakdown of the polyphenol branch of the phytonutrient family as I understand it. (For what it’s worth, I had a couple scientist friends review this.) Polyphenols are a subclass of phenols. They (polyphenols) are split into many groups, including flavonoids, which include flavanols (sometimes called flavan-3-ols) and flavonols (because someone decided switching one vowel in the middle of the word was an effective differentiator). Polyphenols also include the non-flavonoid resveratrol, which is a stilbene.
I’ve read that paragraph dozens of times—I wrote the damn thing—and I still can’t remember it, so here is a simpler take.
Polyphenols are phytonutrients.
Anything starting with “flav” is a polyphenol, with the exception of rappers.
Remembering those two facts will, at least, get you in the door at the Harvard biochem social hour. You can bluff from there because I honestly believe most scientists are as confused as we are.
Which polyphenols should I consume?
For the most part, polyphenols function as antioxidants, which we discussed in the last newsletter. We also discussed how the synergy of all the nutrients in produce (including fruit extracts) supports your body’s internal “endogenous” antioxidants.
Polyphenols also anti-inflammatory. This oxidation/inflammation-battlin’ combo makes them helpful for recovery after a workout because both of these issues play a big role in exercise-induced muscle damage.
Several extracts have been studied and shown to have recovery benefits. Tart cherry, pomegranate, and black currant have gotten a lot of scientific attention. I personally like grape extract because it can be upcycled from the skins and seeds left over from the wine-making process. (I’m a hippy like that.)
While all this science is top shelf, I don’t think you should look to one polyphenol as your recovery silver bullet. Instead, think of polyphenols in general as a silver bullet Gatling gun. Eat tons of fruits (and veggies) and get tons of polyphenols. Rat-a-tat-tat! Favor recovery supplements that use fruit extracts. And if there’s an extract you’re curious about, do some homework—or, better still, ask me and we’ll do the research together.