- 10 Best Polyphenol-Rich Superfoods + Why You Should Be Eating Them
- Why are polyphenols good for you?
- Ready to start working more polyphenols into your diet? Keep reading for 10 foods and drinks that will help you do it.
- 10 foods rich in polyphenols
Top 100 polyphenols. What are they and why are they important?
- What are polyphenols?
- Examples of polyphenols like resveratrol
- What are the top 100
- Best overall foods for polyphenols
- A word of caution
- RELATED: What’s Worse For Your Bod: Sugar Or Salt?
- Red Wine
- 5 foods containing potentially heart-healthy polyphenols
- 8 Foods High in Polyphenols (and Why You Should Add Them to Your Diet)
- 8 Foods Rich in Polyphenols
- The Health Benefits of Polyphenols
- How to Find Foods High in Polyphenols (and Low in Lectins)
- Fruits High in Polyphenols
- Vegetables High Contain Polyphenols
- What About Wine?
- Other Beverages High in Polyphenols
- Signs You May Be Polyphenol Deficient
10 Best Polyphenol-Rich Superfoods + Why You Should Be Eating Them
“Eat food, not too much, mostly plants.” The simplicity and accuracy of those words, written by Michael Pollan in his masterpiece In Defense of Food, are unmatched.
But why are plant-based foods so powerful? Why do I repeat over and over to my heart patients to get seven to 10 servings a day of brightly colored fruits and vegetables? For example, just this week the news channels reported a story that blueberries improve both blood pressure and the healthy flexibility of arteries, making them act younger.
The secret that blueberries and other selected whole foods possess is that they are rich sources of polyphenols. Let’s get to know these powerful chemicals a bit more.
Time to pay attention for a one-minute food chemistry lesson. Polyphenols are a group of plant-based chemicals that have at least one phenol group (don’t ask me why we don’t call some monophenols — I don’t know). One broad type of polyphenols are phenolic acids including red fruits, black radishes, onions, coffees, cereals and spices.
The second broad group are the flavonoids, including isoflavones found in soy, anthocyanidins found in berries and wine, flavones found in herbs, flavonols found in broccoli, tomato and tea, flavanones found in citrus fruits and juices, and flavan-3-ols found in cocoa, tea and wine.
Finally, some famous ones don’t fit into any class, including resveratrol and stilbenes from wine and nuts, curcumin in spices, and lignans in flaxseeds.
Polyphenols improve your health in six ways:
- Lower cholesterol
- Lower blood pressure
- Improve artery (endothelial) function
- Prevent platelet clumping
- Improve arterial flexibility
- Improved life span
The evidence for the heart benefits for foods rich in polyphenols comes from hundreds of studies. One example published last year was a large study in Europe reporting that a higher intake of polyphenols, particularly stilbenes from grapes and nuts and lignans from flax, was associated with a longer life span.
In another recent study, of more than 500 European subjects, healthier arteries were found in those who ate raw vegetables and avoided high-fat dairy products. Consumption of fresh fruit, wine and avoidance of high-fat dairy products was also associated with less inflammation in the same subjects.
Still need more? In over 34,000 post-menopausal women, intake of flavonoid-rich foods such as bran, apples, pears, grapefruit, strawberries, red wine and chocolate was associated with a lower risk of heart disease and all-cause deaths.
Want a few extra tips? The top 100 richest foods in polyphenols has been studied and a list was published, but the top 10 are:
- Star anise
- Cocoa powder
- Mexican oregano, dried
- Celery seed
- Black chokeberry
- Dark chocolate
- Flaxseed meal
- Black elderberry
Honorable mention goes to sage, rosemary, spearmint, thyme, capers, basil, curry, strawberries and coffee.
There is no doubt that food is information. Food can act as a natural medicine, your dinner can determine your destiny, and your fork can decide your fate. Polyphenol-rich foods found in fruits, vegetables, nuts and seeds are a pharmacy to enhance your bodies “chemistry set”, moving the needle away from inflammation and disease and toward healing and vitality. As the deputy director of the USDA said in a rare moment of candor “Eat your damn vegetables,” a path to health, energy and a long life free of illness can be found at the end of your intelligently placed fork.
Photo Credit: Stocksy
Originally posted on MindBodyGreen.com
Why are polyphenols good for you?
Share on PinterestPolyphenols may help to reduce the risk of developing type 2 diabetes.
Many of the health benefits associated with polyphenols may be related to their role as antioxidants. Antioxidants are known for their ability to combat cell damage.
Polyphenols may also impact genes and gene expression. A person’s specific genes can also affect how their body responds to certain types of polyphenols. Polyphenols may even influence gut bacteria.
Type 2 diabetes
Some researchers have reported that polyphenols may lower the risk for type 2 diabetes. Polyphenols may boost insulin sensitivity, as well as slow down the rate the body digests and absorbs sugar.
According to one review, a type of flavonoid called flavan-3-ols may be especially beneficial for lowering insulin resistance. The same review also found that flavonoids seem to be the type of polyphenol most often associated with a lower risk for type 2 diabetes.
An analysis of studies on flavonoid intake and type 2 diabetes concluded that people who consumed the most flavonoids had a lower risk of developing type 2 diabetes than those who took in the least. Increasing flavonoid intake also appeared to be a way to reduce the risk of disease significantly.
Unprocessed cocoa is a rich source of flavonoids. One review found that cocoa consumption significantly decreased a marker of insulin resistance.
It is worth noting that unprocessed cocoa is very different from the chocolate in candy bars or traditional desserts. Unprocessed cocoa comes straight from the cacao plant with no sugar added.
A study in animals looked at the effect of green tea polyphenols on measures of inflammation after exercise.
Rats that received the tea polyphenols were able to keep up their activity for longer than the rats that did not receive the polyphenols. They also had significantly lower levels of chemicals that signaled inflammation and muscle damage in their blood.
Lignans are a class of polyphenols that occur at their highest levels in virgin olive oil, flaxseed, and whole grain rye flour. One way to study lignan intake is to look at levels of lignans in urine.
In a study of adults in the United States, researchers found that higher levels of lignans in the urine were associated with lower levels of measures of inflammation. This could be important since long-term inflammation has been associated with certain diseases, such as heart disease and cancer.
A review of studies looked at the impact of cocoa polyphenols on risk factors for heart disease. Scientists found that consuming cocoa for at least 2 weeks led to a significant decrease in blood pressure.
They also found that cocoa significantly decreased LDL or “bad” cholesterol, and raised HDL or “good” cholesterol.
Polyphenol intake may also play a role in body weight regulation.
One study compared the intake of flavonoids, a class of polyphenols, with body mass index (BMI) and waist circumference. Researchers found that a higher flavonoid intake was associated with lower BMI and waist circumference.
These results are significant because obesity is associated with a higher risk for many chronic diseases
Regardless of what healthy eating plan you stick to, there’s one rule that’s prescribed to all eaters: Eat a lot of plants. If it comes from the ground, chances are it’s good for you. (Okay, except for those mushrooms that will kill you and herbs that are drugs—but even that latter one is hotly debated.) But in general, fruits, vegetables, and herbs have myriad health benefits. One biggie: polyphenols.
“Polyphenols are active compounds that are naturally found in fruits, vegetables, cereals, and some beverages—like wine, coffee, and tea,” says naturopathic and holistic dietitian Meg Hagar, MS, RD. “They benefit the body by fighting against harmful agents like ultraviolet rays, radiation, and some pathogens. Research has shown that diets high in foods rich in polyphenols can even help prevent the development of illness such as cancers, heart diseases, and diabetes.” The ultimate multitasking overachievers, research has also found polyphenols to benefit the body by boosting health in a range of areas including cognitive functioning, cardiovascular strength, and digestion.
According to scientific research, a good goal is to aim to get 650 milligrams of polyphenols a day, though Hagar says the science is a bit fuzzy on this because it’s difficult to measure how well the nutrients are absorbed. “Eating polyphenols will be beneficial no matter what, so get them in whenever and however you can,” she says. “However, since we know they help fight damage, it might be a good idea to be more conscious of consuming these components post-workout, during a day in the sun, or when you have been exposed to environmental pollutants.”
Scientists are starting to investigate polyphenols as a way to slow outward signs of aging too, making it a buzzy nutrient in the beauty industry. “The research supporting polyphenol consumption and anti-aging is fascinating,” Hagar says. “Especially working with a lot of skin clients, I always promote consuming fruits and vegetables for this reason. And it’s also why I’m a fan of moderate tea, coffee, and wine intake.” (All—spoiler alert—top sources of polyphenols, as you’ll soon see.)
Hagar says a good rule of thumb is to get four or five servings of fruits or vegetables a day, not just to reap those polyphenols rewards, but to get the other nutrients you need, too. “This should be more than enough to get the beneficial effects of a high-polyphenol diet,” she says.
Ready to start working more polyphenols into your diet? Keep reading for 10 foods and drinks that will help you do it.
Photo: /CC0 Creative Commons
10 foods rich in polyphenols
All amounts below are per serving, according to the European Journal of Clinical Nutrition.
1. Cherries (274 mg per serving): Cherry on top puns aside, this fruit really brings it on the polyphenols front as one of the highest sources. Scientific studies have linked cherries in particular as being good for your gut, too.
2. Strawberries (235 mg): Just a handful of these juicy berries gets you one-third of the way to the daily goal. One study showed that polyphenols from strawberries can contribute to preventing and treating chronic-degenerative diseases and lower chronic inflammation. (The antioxidants play a big role in that, too.) Just be sure to buy organic since strawberries are the dirtiest of the Dirty Dozen.
3. Red grapes (101-169 mg): Best news ever: This also includes red wine. (You know how you’ve heard that red wine is good for your heart? This is why.) The key—whether you’re going for the fruit in its food form, juice, or wine—is to go for red grapes since the polyphenols are found in their skins. (Green grapes have 10 mg of polyphenols per serving.)
4. Artichokes (260 mg): More into veggies than fruits? Artichokes are a top source of polyphenols. In one study, scientists even used them as a key component in helping treat breast cancer.
5. Red onion (168 mg): Similarly with red grapes, the key here is to go for red onions over yellow ones. You’ll also get more of the benefits if you eat it raw.
6. Spinach (119 mg): Not an artichoke fan? Spinach has a decent amount of polyphenols, too. You’ll also be getting a good amount of fiber, iron, calcium, and vitamin C by adding the green to your plate.
7. Hazelnuts (495 mg): All nuts have polyphenols, but hazelnuts have the most. As for other nuts, pecans have 493 mg of polyphenols and almonds have 187 mg. Your nut milk habit is doing you more good than you thought.
8. Dark chocolate (1664 mg): Your dessert is totally working in your favor—as long as you stay on the dark side and don’t have it every night.
9. Coffee (214 mg): That’s right—your morning cup is full of polyphenols. If you want to get the absolute most, go for a cherry roast.
10. Black tea (102 mg): If you’re a tea drinker, go black; it has a higher polyphenol amount than other varieties, such as white or green.
Looking at this list alone, it’s clear that it isn’t too difficult to meet the daily requirement for the nutrient—especially considering that the sources are delicious. Red wine? Chocolate? Hazelnuts? Done.
While you’re brewing yourself a cup of hot black tea, check out how it’s good for your gut. And here’s how to give it a ketogenic twist.
Top 100 polyphenols. What are they and why are they important?
Generally I don’t pay too much attention to these comparisons for a couple of reasons.
1. The tests vary in what they measure. Results depend on which test is used e.g. ORAC, FRAP, Folin. Also there will be a wide variation in natural antioxidant levels from season to season and variety to variety (red grapefruit vs yellow grapefruit). Nonetheless the same foods appear at the top of each test method – the usual suspects of berries, spices, herbs, tea, cocoa and wine.
2. New European research has identified the top 100 foods for polyphenols. This is a new listing based on the polyphenol content as measured by the Folin assay method which will supercede the rest. You can find all the details on the Phenol-Explorer database.
What are polyphenols?
Many antioxidants are polyphenols so it’s worth knowing a little about them.
Polyphenols are a large class of chemical compounds found in plants. They are characterised by the presence of more than one phenol unit or building block per molecule. A phenol unit consists of a six-membered aromatic hydrocarbon ring, bonded directly to a hydroxyl group (-OH). The simplest of the class is phenol (C6H5OH) which has long been used as an antiseptic. See diagram.
They are also called phenolics. Poly means many, which refers to the large number of groupings of the basic phenol rings. There are over 4,000 polyphenol compounds. Many are powerful antioxidants and can neutralise free radicals, reduce inflammation and slow the growth of tumours.
Here’s the chemical structure of resveratrol which is found in red wine:
Examples of polyphenols like resveratrol
Polyphenols add astringency and bite to foods. You’ll notice it in tea that’s brewed too strong (once called tannins) and in the “greenish” flavour of extra-virgin olive oil or the back palate of red wine. Anything that makes your mouth pucker generally contains polyphenols.
In plants, polyphenols help defend against attack by insects and give plants their colour (anthocyanins).
Examples: resveratrol in red wine, capsaicin in chilli and paprika, thymol in thyme, cinnamic acid in cinnamon, rosmarinic acid found in rosemary, thyme, oregano, sage and peppermint.
What are the top 100
This new research gives you two lists – the first list is the richest 100 foods by concentration, (ie. the number of mg per 100g) while the second comes up with 89 foods ranked by their content per serve. It shows you the best foods and beverages that provide more than 1mg of total polyphenols per serving.
The foods range from 15,000mg per 100 grams for cloves down to a tiny 10mg per 100ml for rosé wine. Many spices and dried herbs appear on this list but not on the Per serve list as their serve size is so small (usually less than a gram or a pinch) that they were excluded.
Think of it this way – while herbs are very concentrated, we use so little that they don’t contribute much in a meal. Although at times we can eat generous amounts of some – think of the amount of parsley you eat in tabbouli salad. Tea on the other hand is ranked only No 52 (black) and No 54 (green) on the Per 100g list but makes it to Nos 16 and 17 in the Per serve list as we drink sizeable quantities (200ml/7oz in a cup).
Best overall foods for polyphenols
By combining the two lists I’ve come up with this general list of the best food sources of polyphenols for each category of foodstuff. I’ve also linked to my Top 20 Super Foods so you can see the commonalities:
Cloves, star anise, capers, curry powder, ginger, cumin, cinnamon
Peppermint, oregano, sage, rosemary, thyme, basil, lemon verbena, parsley, marjoram
Cocoa, green tea, black tea, red wine
Black chokeberry, black elderberry, low bush blueberry, plum, cherry, blackcurrant, blackberry, strawberry, raspberry, prune, black grapes.
Flaxseed, celery seeds
Chestnuts, hazelnuts, pecans, almonds, walnuts
Black olives, green olives
Globe artichokes, red chicory, green chicory, red onion, spinach, broccoli, curly endive,
Fruit other than berries
Apples, apple juice, pomegranate juice, peach, blood orange juice, lemon juice, apricot, quince.
Extra-virgin olive oil, rapeseed (canola) oil
Click to download the two lists: Top foods for polyphenols Per 100g (by concentration) and Per serve.
Reference: Perez-Jimenez J, Neveu V, Vos Fm Scalbert A. Identification of the 100 richest dietary sources of polyphenols: an application of the Phenol-Explorer database. Eur J Clin Nutr 2010; 64(S3):S112-S120.
A word of caution
1. The researchers noted that the Folin method over-estimates the quantity of antioxidant present so these figures look greater than say the ORAC test from the US FDA which has been the biggest database until now. What this means is what I said at the outset – don’t follow the numbers slavishly or base your decision on which fruit or herb to buy by this list. It doesn’t matter whether there’s 20 per cent more or less. It’s the overall ranking that matters.
2. In addition, not all foods with a high antioxidant content have been analysed at this point in time. The authors note the following lack analyses (most are spices or dried herbs) but we’d assume they similar high levels to the ones on the reported list:
dried oregano, dried summer savoury, dried bay leaves, dried camomile, dried coriander, fenugreek, dried winter savoury, pistachio, hyssop, red swiss chard leaves, dried dill, raisin, black pepper, fresh peppermint, fig, fresh lemon balm, fenugreek seed, tarragon, lentils.
Spices in the news
Antioxidant spices reduces triglycerides and insulin response to a high-fat meal
Eating a diet rich in spices, like turmeric and cinnamon, reduces the body’s negative responses to eating high-fat meals, according to US researchers. The researchers added two tablespoons of culinary spices to each test meal, which consisted of chicken curry, Italian herb bread, and a cinnamon biscuit. Spices tested were rosemary, oregano, cinnamon, turmeric, black pepper, cloves, garlic powder and paprika, which were selected because of their potent antioxidant activity. The spiced meal raised the antioxidant activity of the blood by 13 per cent and decreased insulin response by about 20 per cent. Published in the Journal of Nutrition.
Polyphenols might be one of those intriguing buzzwords you frequently read on health food labels. You add them to cart because they sound like something you should be incorporating into your diet but you’re not quite sure why. But…what exactly do they do for you?
Karen Ansel, R.D.N., author of Healing Superfoods for Anti-Aging: Stay Younger, Live Longer, says polyphenols, which are powerful antioxidant chemicals found naturally in many plants, are instrumental in protecting our cells from free radical damage, which are often attributed to chronic illnesses like cancer, heart disease and dementia. They’re linked to longevity, too: A 2013 study published in the Journal of Nutrition found a link between high polyphenol consumption and a 30 percent decrease in mortality in elderly adults.
Want to live long and prosper? Simply eat a plant-heavy diet, which ups your polyphenol ante significantly. You know you should be getting your five to 10 servings of fruits and vegetables a day, but Ansel suggests distributing your plant consumption evenly across every meal, rather than having a green juice for breakfast and calling it a day. “Keep in mind that some polyphenols don’t survive all that long in the body. Eating polyphenol-rich foods at every meal and snack provides the biggest bang by delivering a steady stream to your body all throughout the day,” she says.
RELATED: What’s Worse For Your Bod: Sugar Or Salt?
But because polyphenols aren’t as essential to survival as, say, minerals, there’s no prescribed daily recommended intake. Lifestyle factors, however, can act as a guide. If you smoke or live in a heavily polluted area, Ansel says you need them even more “to help your body quash and protect against the additional free radicals that are attacking your cells.”
You may be tempted to find out the exact polyphenol count in any given food, but that might prove to be fruitless. “Some types of polyphenols aren’t well absorbed or don’t survive well in the body,” Ansel says, “so just because a food is polyphenol-rich, it doesn’t mean you’ll necessarily benefit from its polyphenols.” She adds that many foods have complex mixtures of different kinds of polyphenols, making it impossible to tease out their impact on the body. Sun exposure, storage, cooking methods and ripeness can all affect their count, too.
Over 8,000 different types of polyphenols have been identified, so you probably won’t see that exact term floating around your grocery store on each bottle of pomegranate juice. Instead, watch out for labels that include subclasses of polyphenols like flavonoids, flavonols, and isoflavones.
While the FDA has recently amended regulations to ensure labels accurately represent polyphenol content, your best bet is to opt for fresh produce that also offers plenty of fiber, vitamins, and minerals. Here, the top foods—besides berries!—you should be eating to fill your polyphenol fix that are equal parts delicious and readily available in your grocery store and your pantry.
Keep the skin on your apples to get five times the polyphenols than you would just eating the flesh. As for polyphenol-rich varieties, one study found Red Delicious contains twice the polyphenols than the Empire variety.
This fragrant, spicy seasoning contains the highest polyphenol content of any food, according to the European Journal of Clinical Nutrition. Try them in mulled wine or baked goods for an antioxidant boost.
Red onions are more polyphenol-potent than yellow varieties, according to research. For both, polyphenol content increases the closest to the outer layer you get.
Looking for easy snack options? Check out these 13 delicious ways to spice up a tub of hummus:
While tea has long been touted as practically a pharmacy in a cup, opt for green tea over black for maximum antioxidant benefits, according to a 2010 review.
RELATED: 10 Signs You Have an Iron Deficiency
You could be doing yourself a huge favor by indulging in your daily Starbucks run, but stay away from added sugar and non-dairy creamer, which have been found to negatively impact coffee’s polyphenol absorption, according to a study in the Journal of Nutrition. Milk, however, is in the clear.
Citrus fruits are overall great sources of polyphenols, but the sweet orange’s peel packs the highest amount of all its citrus siblings. Add some actual zest to your desserts to see the benefits, according to this 2016 review.
Note: You’re better off opting for soy in its original bean form (hello, edamame) rather than soy milk for the highest possible polyphenol count—research has found that processing the soy can strip out the polyphenols.
RELATED: 7 Things That Happened When I Ate Beets For Two Weeks
Darker cherries aren’t only sweeter, but they’re higher in polyphenols, according to a 2012 study in the Journal of Agricultural Sciences.
Resveratrol is happy hour’s disease-fighting star. However, this shouldn’t give you carte blanche to drink what you want—most studies emphasize that benefits only come with moderate alcohol consumption.
The polyphenols in cocoa can help with inflammation, heart disease, and cancer, according to this 2010 review. However, beware of the high sugar content found in some bars of chocolate.
Related: What’s Worse For Your Bod: Sugar Or Salt?
Marissa Miller Marissa Miller has spent a decade editing and reporting on women’s health issues from an intersectional lens with a focus on peer-reviewed nutrition, fitness trends, mental health, skincare, reproductive rights and beyond.
5 foods containing potentially heart-healthy polyphenols
There isn’t much dispute about the health benefits of apples. After all, “an apple a day keeps the doctor away,” right? But what about red wine and chocolate?
As it turns out, chemical compounds called polyphenols are found in all three. And, while the jury is still out, there is some evidence that polyphenols may help protect people from a variety of diseases.
Polyphenols occur naturally and are found mostly in fruits, vegetables, cereals, dry legumes, chocolate, some beverages, and spices. They have antioxidant properties and protect plants from ultraviolet radiation.
The word “antioxidant” can make people feel good, but the reality of whether antioxidants provide health benefits is much more complex. Some preliminary research suggests that diets rich in foods containing polyphenols could potentially offer some protection from the development of cancer, heart disease, diabetes, osteoporosis, and neurodegenerative disease, but we must weigh initial findings such as these with clinical results.
We’ve seen numerous instances in which changes in a biomarker, such as cholesterol levels, do not necessarily translate into clinical benefit. So far, no clinical studies to track changes in disease burden and patient longevity have not been conducted to evaluate the true benefit of antioxidants.
Several studies have focused on polyphenols over the past 20 years. When it comes to heart disease, some research suggests that polyphenols may improve the function of the inner lining of the blood vessels, increase protective HDL cholesterol (the good cholesterol), and promote anti-platelet and anti-inflammatory activity.
Below is what preliminary research suggests – and what we truly know – about the health benefits of five polyphenol-rich foods:
- Red wine
- Olive oil
Both the skin and flesh of apples contain polyphenols. Researchers have tried to determine which parts of the apple affect cholesterol levels, but we don’t have a concrete answer yet.
One randomized, placebo-controlled study indicated that the polyphenols in apples may result in a health benefit. Specifically, the study suggested that a diet supplemented with apple polyphenol extract resulted in lower cholesterol.
However, a more recent study leads us to believe that the soluble fiber in apples may be driving cholesterol benefits. The study compared eating whole apples (which contain polyphenols and soluble fiber) to drinking apple juice (which contains only polyphenols). Researchers found that eating the apples significantly reduced total cholesterol but drinking the juice did not.
These two studies are not “apples-to-apples,” though. In the initial study, the polyphenols were more concentrated than in the more recent study. That difference may have impacted the results.
Also, one would have to drink an enormous amount of juice to see any relevant antioxidant activity. The amount of sugar and calories in the juice would most likely offset any potential antioxidant benefit.
Bottom Line: Whether it’s the soluble fiber or a combination of soluble fiber and polyphenols doing the good work, apples contain both potentially protective substances. They’re convenient, filling, and a delicious, sweet treat – one of nature’s great “fast foods.”
Red wine and dark grape juice contain a specific kind of polyphenol called resveratrol. Researchers have discovered that resveratrol:
- Decreases inflammation
- Stimulates the production of nitric oxide, which,
- Signals the arteries to expand, easing blood flow
You may have heard that red wine is good for your heart, and it’s true, when consumed in moderation. Red wine is one of the components of the heart-healthy Mediterranean diet. Similar to apple juice, one would likely have to consume several bottles of wine to experience antioxidant benefits from resveratrol – and drinking that much alcohol is in no way heart-healthy.
Bottom Line: If you drink, do so in moderation. If you are on medication, drink only after discussing it with your doctor. Moderate alcohol consumption is defined as one drink per day for women and two per day for men. One drink equals a 5-ounce glass of wine, a 12-ounce beer, or 1.5 ounces of liquor.
Several studies have examined whether chocolate provides heart-healthy benefits. One large observational study has linked eating milk chocolate or dark chocolate in moderation to a lower risk of heart disease and stroke.
Milk chocolate and dark chocolate contain flavonoids, a kind of polyphenol that is associated with heart health. But dark chocolate contains much more flavonoids than milk chocolate.
Some research suggests that eating small amounts of dark chocolate that is 70 percent or higher in cocoa reduces blood pressure and LDL cholesterol and also improves cognition. Again, a clinical study to track changes in patient health and longevity over time would be necessary to determine any true benefits of flavonoids found in chocolate.
Bottom Line: Just because chocolate may have some health benefits doesn’t mean it’s OK to have a candy bar every day. Most experts recommend no more than 1 ounce per day of chocolate, which averages 170 calories.
8 Foods High in Polyphenols (and Why You Should Add Them to Your Diet)
8 Foods Rich in Polyphenols
1. Dark chocolate. Boasting a whopping 1,664 mg of polyphenols per serving, we’re definitely using this as an excuse to indulge in a few squares of the dark stuff for dessert tonight (just don’t go crazy—sugar isn’t so good for you, remember?).
2. Hazelnuts. While all nuts contain polyphenols, hazelnuts top the list with 495 mg per serving (followed by pecans and almonds).
3. Cherries. You already know that this tart fruit can help you sleep, but did you know that it’s also a polyphenols powerhouse? With 274 mg per serving, we’ll be picking up an extra batch of these at the farmers market this weekend. (And the darker the cherries the better, according to a 2012 study in the Journal of Agricultural Sciences.)
4. Artichokes. With 260 mg of polyphenols per serving, there’s no better reason to whip up these crispy roasted artichokes with garlic aioli.
5. Strawberries. Our favorite summer snack boasts 235 mg of polyphenols per serving. Stick to organic berries if possible, since these guys are high on the Environmental Working Group’s dirty dozen.
6. Coffee. Best. News. Ever. Your morning cup of joe has 214 mg of these antioxidants per serving. Just stay away from added sugar and non-dairy creamer, which can actually negatively impact coffee’s polyphenol absorption, according to a study in the Journal of Nutrition.
7. Red grapes. Scratch that—this is even better news. While the fruit contains 169 mg of polyphenols per serving, red wine has 101 mg. We’ll take another glass of merlot, please. Note: Polyphenols are found in the skins of red grapes—green grapes (used for white wine) have just 10 mg of polyphenols per serving.
8. Spinach. Add some of these green leaves to your salad for an extra 119 mg of polyphenols per serving. Plus, loads of good-for-you nutrients and vitamins, of course.
Amounts of polyphenols per serving, according to the European Journal of Clinical Nutrition.
Teeming with antioxidants that support anti-aging, brain function and heart health, polyphenols are the latest micronutrient scientists are urging you to add to your diet. But what are they and where can you find them?
Dietary polyphenols appear in various natural foods, such as fruits, vegetables, lectin-free cereal grains like millet, tea and wine. They are not just responsible for giving fruit and vegetables their distinct colors and aromas—they also have numerous health benefits, including protecting our bodies from free radical damage and ultraviolet radiation, shielding our cardiovascular system, reducing inflammation and promoting brain health.
To figure out what foods have polyphenols, consider the four types of this micronutrient: flavonoids (includes fruits and legumes), stilbenes (such as in peanuts), lignans (from seeds, cereals and algae) and phenolic acids (found in cinnamon and tea).
Learn more about how polyphenols might enhance your health and start integrating polyphenol-rich foods and beverages into your diet.
The Health Benefits of Polyphenols
Over the last decade, interest has grown in the potential health benefits of polyphenols as an antioxidant. Oxidative Medicine and Cellular Longevity, confirms that long-term consumption of diets rich in plant polyphenols offer protection against the development of cancers, cardiovascular diseases, diabetes, osteoporosis and neurodegenerative diseases. The structure of polyphenol compounds found in green tea is also linked to protecting skin from ultraviolet radiation and having anti-inflammatory properties. And in a study from the Icahn School of Medicine at Mount Sinai, scientists found that grape-derived polyphenols can even protect against depression. Women struggling with menopause symptoms also found relief when consuming polyphenols.
How to Find Foods High in Polyphenols (and Low in Lectins)
The top 10 polyphenol-rich foods according to Dr. Joel Kahn, a cardiologist and advocate of plant-based nutrition, are:
- Star anise
- Cocoa Powder
- Mexican oregano, dried
- Celery seed
- Black chokeberry
- Dark chocolate
- Flaxseed meal
- Black elderberry
But don’t let this list limit you. According to Dr. Stephen Gundry, who has written extensively on the health benefits of polyphenols, there are numerous food sources we can look to for high polyphenol content like berries, vegetables, tea and wine. But we should steer clear of lectins, such as beans, peas, lentils, nuts, squash, nightshade vegetables (eggplant, peppers, potatoes, and tomatoes), whole grains (especially whole wheat), dairy and eggs. He told Reader’s Digest, “Lectins bind to sugars on the walls of the intestines. In the gut, lectins flip a switch that creates a space between intestinal cells, allowing bacteria and lipopolysaccharides (LPS) to cross the gut wall.”
Fruits High in Polyphenols
According to Gundry, fruits with high polyphenol content include:
- Dark berries
- Black chokeberries
- Black elderberries
- Black Currants
But Gundry advises that we exercise caution when eating fruit, always eating it in-season and not overdoing it. “Eating fruit in-season was a great thing for our ancestors because it allowed them to fatten up for the winter months,” he notes. “But now, we can get fruit any day of the year. So, we have to be sure to consume it in moderation.”
Vegetables High Contain Polyphenols
Vegetables with the most polyphenols are:
- Black olives
- Green olives
- Jerusalem artichokes
- Red chicory
- Green chicory
- Red onions
- Curly endive
What About Wine?
Red wine, which contains around 10 times more polyphenols than white, has been shown to significantly reduce the risks against diseases and some types of cancer as found by researchers at the University of Vienna. Drinking one glass of red wine a day slashed men’s risk of prostate cancer by around 12 percent, the study reports. Gundry suggests, when it comes to polyphenol-rich wines, reach for:
- Cabernet Sauvignon
- Petite Syrah
- Pinot Noir
Other Beverages High in Polyphenols
Different types of teas contain different types of polyphenols, but research has found that tea polyphenols account for about 30 percent of fresh leaf dry weight. The study also links green tea consumption to the prevention of many types of cancer, including lung, colon, stomach, mouth, small intestine, kidney, pancreas and mammary glands.
Signs You May Be Polyphenol Deficient
Think you may be polyphenol deficient? Gundry offers these signs of potential polyphenol deficiency: muscle fatigue, stiff joints, cloudy vision, nausea and shortness of breath. With sources as natural as berries, vegetables, nuts and tea, it shouldn’t be difficult to turn things around.
Erica Garza is an author and essayist. Her work has appeared in TIME, Health, Glamour, Good Housekeeping, Women’s Health, The Telegraph and VICE. She lives in Los Angeles.
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