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Can an apple a day really keep the doctor away? How about red wine and chocolate? They might! All three contain compounds called polyphenols — plant compounds with very strong antioxidant properties that are quite beneficial to your health.

So pour that glass of wine and chop up an apple, here’s what polyphenol foods can do for you.

Polyphenols are a class of chemicals found naturally in plants, including fruits, veggies, herbs and spices, teas, cocoa, and even wine.

These chemicals are designed to protect plants from threats, like UV radiation and insects. Not surprisingly, they help protect your health as well. This is mainly due to their antioxidant and anti-inflammatory power.

Science continues to point to the protective benefits of polyphenols, including:

  • lowering blood sugar
  • preventing blood clots
  • lowering risk of heart disease
  • preventing cancer
  • improving digestion
  • reducing asthma and improving lung damage
  • improving brain function

There are thousands of polyphenol compounds in existence, but the general categories under the polyphenol umbrella, include:

  • Flavonoids. These make up 60 percent of polyphenols and include anthocyanins, catechins, kaempferol, and quercetin. Found in apples, asparagus, dark chocolate, red cabbage, and onions.
  • Phenolic acids. These make up 30 percent of polyphenols and include stilbenes and lignans. Found in fruits, vegetables, whole grains, and seeds.
  • Polyphenolic amides. Includes capsaicinoids and avenanthramides. You can find capsaicinoids in chili peppers and avenanthramides in oats.
  • Other polyphenols. Includes resveratrol (red wine), ellagic acid (berries), curcumin (turmeric), and lignans (whole grains, flaxseed, and sesame seeds).

How much polyphenol and the type you get in your snack, totally depends on the food. Plus what happened along the way from the farm to food prep.

There are hundreds of foods that contain polyphenols in some form. Here are some simple foods to add to your plate to get some polyphenol goodness.

Apples

Apples contain a whole bunch of polyphenols (136 milligrams of polyphenols, to be exact). These act as strong antioxidants. Epidemiological studies have linked apple consumption with reduced risk of certain cancers, heart disease, asthma, and diabetes.

How to eat ‘em

Eating apples the old fashioned way is best (wash and eat them raw). Processing messes with the polyphenol content so skip the fruit snacks and go for the real thing. It’s especially important to eat the skin to get those polyphenols.

Blueberries

If foods could wear accessories, blueberries would wear a crown. Berries in general are loaded with polyphenols via antioxidants.

The polyphenols in blueberries can help protect your nervous system from damage. And, they may enhance cognitive functioning and help prevent cardiovascular disease by way of their antioxidant and anti-inflammatory properties.

How to eat ‘em

There’s no wrong way to enjoy blueberries. Add them to oatmeal, plain Greek yogurt, a smoothie — heck, use them as an ice cream topping.

Black and green tea

Both green and black teas contain polyphenols in the form of flavonoids. Green tea is known for its rich epigallocatechin-3-gallate (EGCG) content and black tea for its theaflavin content (which both fall under the polyphenol umbrella).

Both are great for heart health and reducing LDL cholesterol (the “bad” kind) and triglyceride levels (also bad at high levels). EGCG in particular may help you feel more calm, less fatigued, and even help prevent cancer cell growth and Alzheimer’s disease.

Tea catechins have also proven to be particularly beneficial to help keep blood sugar levels in check. The theaflavins in black tea have also been found to help prevent and treat asthma and chronic lung disease.

Drink up!

Are you suddenly craving a matcha latte? Tea is pretty simple. Make a hot cuppa or drink it iced.

Black beans

Black beans are a great source of polyphenols. In addition to being a rich source of nutrients like protein and fiber, they are packed with antioxidants and may help keep blood sugar levels under control.

How to eat ‘em

Throw some black beans on a salad, make them into a burger, or mash them up into a dip with herbs and spices.

Soybeans

Soybeans are full of isoflavones, a type of flavonoid. They’re the compounds that give soy its antioxidant muscle, scavenging free radicals and reducing inflammation (you go, soybeans).

How to eat ‘em

Minimally processed is the way to go here — think edamame, organic tofu and tempeh to reap the antioxidant benefits of these powerful beans.

Red wine

Resveratrol (found in red wine) has proven to be protective from a number of chronic health conditions, including diabetes and heart disease. Per general health recommendations, one to two drinks per day (without binge drinking!) may help protect against coronary disease and stroke.

Resveratrol may also be beneficial in the prevention of blood clots by making platelets less likely to stick together and form a clot. Plus, studies show resveratrol can improve insulin sensitivity and regulate glucose absorption in the gut.

Drink up!

This is not a recommendation to down a bottle of Pinot Noir every night, but a few glasses a week could do your health some good.

Asparagus

This veggie is full of flavonoids like quercetin, which is believed to help prevent certain types of cancer and coronary heart disease.

In animal studies, quercetin (and resveratrol in red wine!) have demonstrated beneficial effects in prevention and delayed progression of lung cancer.

How to eat ‘em

Asparagus comes in different colors like green, white, or purple. But, if you’re looking for the most antioxidant rich variety, it’s green all the way.

Toss asparagus spears in olive oil and grill or roast them until they’re a little bit crispy. You can also add chopped asparagus to omelets or add shaved raw asparagus spears to your summer salad.

Extra virgin olive oil

EVOO is a staple in the Mediterranean diet, you know the diet that boasts a ton of anti-inflammatory benefits? Well, extra virgin olive oil is part of that claim.

Unlike regular olive oil, EVOO is made of cold-pressedolives (not a mix with processed oils) that helps you reap its natural benefits.

A study comparing EVOO to regular olive oil and corn oil, found its polyphenol content may help reduce “bad” cholesterol levels and has been shown to significantly decrease inflammatory markers.

Get your oil on

Use it in a salad dressing or toss your veggies in it. And yes, go ahead, dip that bread basket in EVOO in the name of health.

Spinach

Spinach is packed with powerful antioxidants like vitamins A and C, fiber and even some protein. Spinach offers a lot in the health benefits department, but it’s free radical-fighting polyphenols may specifically help to lower cholesterol and battle inflammation throughout the body.

How to eat it

Spinach is versatile and can be used in a variety of ways. You could toss a handful into a smoothie, or an easy way to use it is as a (nutrient rich) salad base.

Walnuts

These nuts are already well known for their essential fatty acid content, but they’re also rich in a type of polyphenol called ellagitannin.

Ellagitannins have been studied for their potential role to reduce the risk of certain diseases including cancer, cardiovascular diseases, and neurodegenerative diseases.

How to eat ‘em

Eat walnuts like candy (just not actually candied) or throw them on a salad. Have you tried walnut butter yet?! If you’re not ready to invest in a jar of the stuff sight untasted, throw some walnuts in a food processor and make your own (that ish is delish 🤤).

Cocoa and dark chocolate

What food list would be complete without chocolate? Cocoa is one of the top sources of polyphenols in the food kingdom. And, it’s particularly beneficial for your ticker by helping to prevent heart disease, high cholesterol, and high blood pressure.

How to eat ‘em

While it’s true that processing cocoa does reduce it’s polyphenol content, including small amounts of high quality cocoa and dark chocolate with at least 70 percent cacao content into your regular routine still offers plenty of disease fighting power.

Cinnamon

Cinnamon is a powerful polyphenol spice that slows down the process of digestion and halts blood sugar spikes. Studies have shown cinnamon also helps to reduce blood sugar levels in patients with type 2 diabetes.

Sprinkle it!

Put some cinnamon on your toast, on your oatmeal, even in your coffee.

Ermmm… probably not. Questions still exist as to the benefits and effectiveness of polyphenol supplements, and the supplement industry is still unregulated. It’s unclear if they’re as effective as the real thing.

Bottom line: We need more research to determine the safest and most effective dosages of these supplements, so proceed with caution.

Get your fruits and veg

These supplements should not (repeat, should not) replace eating healthy nutrient-rich foods.

Foods rich in polyphenols are safe to eat for most people (unless you have an existing allergy or intolerance). Supplements are a different ball game.

Some supplement brands recommend doses 100 times higher than what is typically consumed through foods.

Risks associated with high-dose polyphenol supplements include:

  • damage to the liver and kidneys
  • inhibiting thyroid function
  • acting as anti-nutrients (blocking absorption of important nutrients we need)
  • potential medication interactions
  • potential carcinogenic effects

tl;dr

  • Foods rich in polyphenols are fantastic for health and should be included as part of a balanced, healthy diet.
  • The best way to reap the rewards of these nutrition gems is through whole foods, hands down.
  • There is no scientific consensus around appropriate dosing for these compounds as of yet, so supplements should be considered with caution.
  • The supplement industry remains unregulated, and some products may provide excessive amounts of polyphenols, potentially causing harm.
  • If you’re thinking about trying a polyphenol supplement, be sure to speak with your healthcare provider or pharmacist first.