If you have read recent post onto phytochemicals, then you know that crops are complete powerhouses of health-promoting compounds – above and beyond the critical vitamins, minerals and fiber they’re already famed for. However, one type of phytochemical is this a standout concerning diversity, breadth, and importance it warrants its very own blog post: yep, I am speaking about polyphenols!
The following week, the World Health Organization classified processed and red meats as carcinogenic (and more details from WHO here, along with my responses here and here). Especially, processed meat consumption was labelled as IARC Group 1 (the International Agency for Research on Cancer label for “carcinogenic to humans”) on the basis of sufficient evidence for colorectal cancer, and supported by an association with prostate cancer. Red meat consumption was labelled as IARC Group 2A (the label for “probably carcinogenic to humans”, only one notch under Group 1) on the basis of epidemiological data showing a positive association between consumption of red meat and pancreatic cancer, pancreatic and prostate cancer.
So, processed meat only got put into exactly the same category of substances as smokes, benzene, and mustard gas. And red meat only got put into exactly the same class as acrylamide, direct, and urethane. That’s pretty extreme, and definitely worthy of detailed discussion!
Yet, studies that look at both beef along with vegetable consumption reveal that the problem comes from heavy processed and red meat consumption just in the absence of substantial vegetable consumption in the diet. And, this can be a significant distinction because it means that dietary choices with cancer avoidance in mind should not worry about decreasing meat consumption per se, but rather increasing veggie parts. I talked about the connection between cancer and meat as well as how vegetables fit into the equation at this recent post.
Comment: As is often pointed out, research connect meat consumption to cancer, whether processed or red meats, don’t generate a differentiation between sterile, pastured raised meats and also the factory-farmed, glyphosate laden, compound agriculture-based “beef” generally absorbed by the populace. While radicals certainly are a great concept to counteract general environmental damage, picking “good meat” is also crucial to protecting your wellbeing.
One of the more provocative pictures that went viral at the deluge of responses to this WHO’s determination of meats as inducing cancer.
How is this related to polyphenols? As you’ll read below, among the major beneficial properties of polyphenols is they have a tendency to be quite good at both fighting and preventing cancer (there’s lots of other amazing health advantages that I will get to too!) . In the wake of the last week’s media frenzy and the impassioned responses that blew the world wide web, I feel that it’s very important to focus the debate about why vegetable ingestion is so crucial.
Beyond how compounds in vegetables directly interfere with the carcinogenic activities of processed and red meat (clarified here), and even past the critical nutrients that plant-based foods can supply that we just can not gain from animal foods (explained here) plants have been rife with compounds that are essential for wellbeing however not considered necessary for life. That means that while we will not expire if we do not consume adequate amounts of phytochemicals in our diet (discussed in this article), we are not likely to achieve optimal health and live a lifetime. No matter your health targets, polyphenols will allow you to achieve them. And, given this dark cancer cloud looming over processed and red meat, polyphenols an incredibly important example of just why it’s essential to embrace vegetable consumption and prioritize it (along with beef!) In our diets. So, let’s talk about these remarkable compounds in detail!
Which are polyphenols, exactly?
Polyphenols are a class of over 8,000 substances with antioxidant properties. In actuality, that our consumption of polyphenols is greater than any other kind of vitamin or hepatitis! However, due to their diversity and complex chemical structures, polyphenols didn’t get much scientific attention until relatively recently (in comparison to other plant chemicals such as antioxidant vitamins). As a result, we have a long way to go before we fully understand how polyphenols apply their health-supportive effects.
For those plants that include antioxidants, them help safeguard against sunlight damage (from ultraviolet rays), deter herbivores, prevent microbial infections, and supply pigmentation (color). And for us people, polyphenols play with quite a few significant roles also. Even though polyphenols aren’t considered “essential nutrients” (meaning we need them to remain alive), numerous lines of evidence – from epidemiological studies, individual trials, animal models, and mechanistic research – all imply that polyphenols play a enormous role in protecting against cancer, cardiovascular disease, diabetes, asthma, osteoporosis, neurodegenerative diseases, and other ailments associated with oxidative stress. In actuality, a significant reason foods such as red wine and olive oil (as well as diets rich in both, like the Mediterranean diet) show up as so beneficial may be caused by their high polyphenol content! And, along with chronic diseases, supplementing with antioxidants has been proven to protect against diseases and decrease the signs of aging. How amazing is that?
© Pandey KB & Rizvi SI, 2009.
How Can Polyphenols Work?
In the human anatomy, polyphenols – based on the particular type – could be consumed directly into their naturally occurring form, broken down by intestinal enzymes, or transformed into active metabolites by gut bacteria. In any of these situations, once the polyphenols (or their metabolites) finally make it across the gut and enter the bloodstream they could collect in tissues all over the body. That’s where their health-boosting properties have a chance to shine!
Polyphenols apply their powerful effects by performing as antioxidants-preventing mobile damage by neutralizing toxic oxygen radicals, and improving mobile health as a result (that, in turn, benefits practically every system in our body) . As a result of the anti inflammatory properties, polyphenols also enhance the immune system and protect against both chronic and acute diseases. However, that’s just the start of these strong molecules operate their magic! Polyphenols can also help modulate receptor function, stimulate cell receptors, modulate the functions of inflammatory cells (such as T and B lymphocytes, macrophages, platelets, and natural killer cells), change adhesion receptor expression, influence nerve cells and cardiac muscle cells, and execute antiviral effects. Each one these results translate to polyphenols’ amazing disease-protective properties exhibited over and over from the scientific literature.
What Kinds of Polyphenols Are You?
From a chemical perspective, polyphenols have been widely defined as molecules that have several phenols (hydroxyl groups bonded to aromatic rings). But again, that contains literally thousands of unique molecules! So when we speak about polyphenols, it’s easier to group them into categories according to their chemical structure and general characteristics.
© Pandey KB & Rizvi SI, 2009
That leaves us with four main categories: phenolic acids, including stilbenes, lignans, and flavonoids (which contain six extra subcategories-flavonols, flavan-3-ols, flavones, isoflavones, flavanones, and anthocyanidins). Let us take a look at each one of these!
Phenolic acids are strong antioxidants that can be divided into two categories: derivatives of cinnamic acid (such as caffeic acid and ferulic acid), and derivatives of benzoic acid (such as gallic acid). The highest sources of phenolic acids are tea (abundant in gallic acid), java (abundant in caffeic acid), plus some fruits (like blueberries, kiwis, cherries, plums, and apples). Levels of benzoic acid appear to have powerful antimicrobial properties, and some research suggest that cinnamic acid derivatives can protect against cardiovascular disease by enhancing cholesterol efflux from macrophages.
© Uto-Kondo H, et al..
From Uto-Kondo H, et al. “Coffee consumption enhances high-density lipoprotein-mediated cholesterol efflux in macrophages.” “Figure 2. Caffeic and ferulic acid raise the term of ABCG1 and SR-BI in macrophages.”
Stilbenes aren’t found in very significant levels in many foods, however one special stilbene – based resveratrol – had repeatedly demonstrated up from the scientific literature as with powerful anti-cancer properties. Together with its antioxidant effects, resveratrol can impair each of three stages of cancer development (initiation, promotion, and development) by modulating the pathways involved in cell division, cell growth, cell death, inflammation, and angiogenesis (the development of new blood vessels), and metastasis (the spread of microbes). Pretty powerful, huh? Resveratrol is a significant reason red wine (as well as the blossoms it’s made from) is firmly disorder protective: the most abundant supply is grape skins! Other stilbenes such as rhapontigenin, pinosylvin, and pterostilbene (an analog of resveratrol, and the main antioxidant in polyphenols) are also being explored for their potential to protect against (or fight present) cancer, and neurological diseases, inflammation, diabetes, and cardiovascular disease, and stroke.) In actuality, pterostilbene is appearing as possible treatment for Alzheimer’s disease!
Lignans are a type of fiber-associated polyphenol that get transformed by gut microbes into enterodiol or even enterolactone. Some evidence suggests that enterolactone, in particular, can inhibit the growth of breast cancer along with other hormone-associated cancers (possibly by modulating estrogen signaling and acting as a phytoestrogen – that are plant compounds structurally similar to estradiol). Other studies suggest a role for lignans in reducing inflammation, improving glycemic control, combatting viruses, viruses, and protecting against cardiovascular disease, but we need more study and greater – controlled human trials to better clarify if lignans are accountable versus other elements of plant foods! The most popular sources of lignans are flaxseed and sesame seed, and lignans can be found in smaller amounts from cruciferous vegetables (such as cabbage and broccoli), soy, apricots, along with berries.
Out of all of the classes of antioxidants, polyphenols are the most intensively studied. And for good reason: You will find more than 4,000 varieties of these, and they’re present in a enormous assortment of plant foods! Even though most polyphenols exert their greatest effects by working as antioxidants, flavonoids can help modulate cell-signaling pathways independently of antioxidant action – in turn reducing inflammation, and protecting against cardiovascular disease and certain cancers, and combating bacterial and viral diseases.
The six categories of flavonoids are flavonols, flavan-3-ols, flavones, isoflavones, flavanones, and anthocyanidins, each using their own distinct properties.
Flavonols: Flavonols will be the most abundant sort of flavonoid, and contain the well-studied quercetin and kaempferol, as well as myricetin. Though the very low bioavailability of quercetin makes it look more remarkableat vitrothan once eaten by humans and other animals, itdoesappear to suppress inflammation in the brain.
Kaempferol may interrupt the rise of multiple types of cancer, and reduce heart disease risk, and exert anti inflammatory, neuroprotective, antidiabetic, anti-osteoporotic, anti-anxiety, pain-relieving, and anti-allergic properties! Likewise, the flavonoid myricetin can protect cells from carcinogenic mutations, inhibit viral action, and protect neurons from oxidative stress.
In general, the most abundant sources of flavonols are onions, curly kale, leeks, broccoli, and blueberries, and flavonoids have a tendency to get concentrated at the outer tissues of plants (such as fruit skin and the dark outer leaves of cabbage and lettuce) since this sort of polyphenol is synthesized in response to mild stimulation. (Put simply, eat these fruit skins)
Flavan-3-ols: Flavan-3-ols (also known as flavanols, not to be mistaken by flavonols using 2 o’s!) Occur in two types, catechins and proanthocyanidins (also called condensed tannins). Catechins are observed in many kinds of fruit (apricots would be the most abundant source) as well as red wine and green tea, and proanthocyanidins are the things provide particular foods and beverages their astringency-including wine, tea, grapes, peaches, berries, pears, along with bitter chocolate. Flavan-3-ols play an significant role in vascular health by supporting normal blood flow and maintaining the elasticity of arteries, and they can also have anti-microbial, anti-carcinogen, along with neuro-protective properties.
Flavones: Flavones are a less-common flavonoidluteolin and consist chiefly of luteolin and apigenin. With the exclusion of parsley and celery, they’re mainly found in foods sources most of us do not eat (such as citrus skin).
Isoflavones: together with lignans, isoflavones are considered phytoestrogens due to their structural similarities to true estrogens – that provides them the capability to bind to estrogen receptors and exhibit anti-inflammatory properties. (Whether this has a positive or adverse impact on health is an ongoing argument!) The principal sources of isoflavones are beans (in particular, soybeans).
Flavanones: By much, citrus fruits boast the highest concentration of flavanones from any foods! But, tomatoes and mint also comprise them in smaller amounts. While we need more study to understand and confirm that their consequences in individuals, flavanones appear to be very cardio-protective, anti-inflammatory, anti-hypertensive, and even effective at raising insulin sensitivity.
Anthocyanidins: The next time you marvel at the gorgeous blue, purple, blue, or heavy crimson color of a vegetable or fruit, know that we have anthocyanidins to thank you for this vibrant hue! Together with giving particular plant foods that their rich coloration (especially blossoms, red cabbage, peas, many berries, and eggplant), anthocyanidins may have neuroprotective effects and anti-inflammatory properties. Additionally, This Sort of flavonoid comes with an affinity for pain-sensation cell membranes in the brain, giving it the potential to act as a nuisance reliever.Richest Sources of Polyphenols
Though a lot of foods are packed with specific polyphenols (such as the ones mentioned above), it’s also fantastic to have a summary of the highest-polyphenol foods overall (since in the event of polyphenols, more is better!) . In 2010, French researchers examined tens of thousands of pieces of data to identify the total polyphenol content of various foods. From there, they put together a listing of those best 100 richest sources (according to milligrams of g per 100 g of food, or 100 ml of drink).
Are you ready to ramp up your consumption of polyphenols? Check out these superstars!
- Different herbs and spices. Simply seasoning our meals with tasty herbs and spices can considerably increase our meal polyphenol content! Several standout seasonings contain: star anise (5460 mg of g per 100 g), dried oregano (2319 milligrams per 100 g), celery seed (2094 milligrams per 100 g), dried sage (1207 milligrams per 100 g), dried rosemary (1018 milligrams per 100 g), dried thyme (878 milligrams per 100 g), capers (654 milligrams per 100 g), dried sweet ginger (322 milligrams per 100 g), and dried ginger (202 milligrams per 100 g). (These herbs and spices are full of polyphenols when refreshing, too, however, their polyphenol content grows more concentrated when they’re dried on account of the removal of water.)
- Other heavy blue, purple, black, or reddish fruits. Together with berries, an assortment of other vibrant fruits might help us raise our polyphenol consumption. Purple plums have 377 milligrams of polyphenols per 100 g, sweet cherries have 274 milligrams per 100 g, black blossoms have 169 milligrams, and darkish red apples consuming 136 mg.
- Nuts. Certain nuts are really high in polyphenols, including chestnuts (1215 milligrams per 100 g), hazelnuts (495 milligrams per 100 g), pecans (493 milligrams per 100 g), and almonds (187 milligrams per 100 g). And, that usually means that butters made from such nuts are also great polyphenol sources!
- Mint. Even though there are actually over 600 types of mint out there, the two most common for cooking (or even beverage-making) happen to be excellent sources of polyphenols. Dried peppermint has 11960 milligrams of polyphenols per 100 g, and dried spearmint has 956 milligrams per 100 g. Yum! (And yep, this usually means that mint herbal infusions can also be high in polyphenols.)
Variety is Essential
Certainly, polyphenols are pretty darned amazing – and the fantastic news is there are a great deal of delicious, polyphenol-rich veggies, fruits, nuts, spices, herbs, and beverages to pick from! Even better, loading our plates with brightly colored (and deliciously seasoned) meals means people can delight in the many perks that this type of phytochemical can deliver.
As for if polyphenols qualify as a magic bullet, then not. They’re clearly critical for optimal health and wellbeing, but there’s no evidence they’re a cure-all. That’s not meant that their supposed advantages are overblown wellness hype though! In actuality, the scientific evidence is unequivocal: polyphenols will be da bomb!
From combating cancer (and negating the possibly deadly properties of red meat) to reducing risk of cardiovascular disease, diabetes, asthma, osteoporosis, neurodegenerative diseases, and even aging, even a diet abundant in an array of polyphenols (or rather the fruits and veggies that comprise them, as well as other amazing phytochemicals, vitamins, minerals and fiber!) Is where it’s at!