Medical studies find that flavonoids reduce risk of cancer!
Although we're not claiming that the flavonoids in palo azul can cure cancer... we thought it would be worth sharing the abundant evidence we found on the cancer-inhibiting effects of flavonoids.
Before we go on...What are flavonoids?
Flavonoids are natural products commonly found in vegetables, fruits, plants, bark, flowers, wine and tea such as Palo Azul.
There’s a ton of studies that have found numerous health benefits in flavonoids and these are are attributed to their anti-oxidative, anti-inflammatory, anti-diabetic, anti-aging, anti-hypertensive, anti-bacterial, anti-mutagenic, anti-viral and anti-carcinogenic properties.
Learn all about Flavonoids here
In fact, we read two medical reviews composed of findings from 327 studies done specifically on flavonoids, and found that oxidative stress can lead to cancer, diabetes, cardiovascular disease, and aging ... For this reason, they found that antioxidants show potential to fight these diseases.
Therefore, diets rich in antioxidants decrease the cancer-promoting action of free radicals and oxidative stress.
One of the studies we reviewed found that fruits and vegetables that have flavonoids have been reported as cancer chemopreventive agents and are inversely associated with cancer incidence.
What is oxidative stress?
Oxidative stress is an imbalance between free radicals and antioxidants in the body.
What are free radicals?
Free radicals are atoms with a single valence electron that cause damage to the body associated with diabetes, cancer, aging, atherosclerosis, Parkinson's, Alzheimer's and many other diseases.
This happens because electrons like to be in pairs... and for this reason, free radicals look for "free" electrons in the body. This causes damage to cells, proteins, DNA and these damaged molecules can mutate, grow tumors, and damage the DNA code. Eventually, this cellular damage causes new cells to grow with defects and it will lead to aging and degenerative diseases.
It is well documented that oxidative stress can cause cancer, diabetes, cardiovascular diseases, aging, and thus... “potent antioxidants show potential to combat progression of carcinogenesis. Therefore diets rich in radical scavengers would diminish the cancer-promoting action of some radicals [134].”
Due to these findings, it’s no surprise that “fruits and vegetables having flavonoids have been reported as cancer chemopreventive agents.”
These are the MOST flavonoid-rich foods: apples, pears, onions, strawberries, blueberries, celery, peppers, and teas such as palo azul
In fact!...this same study mentioned that the“consumption of onions and/or apples, two major sources of the flavonol quercetin, is inversely associated with the incidence of cancer of the prostate, lung, stomach, and breast.”
The researchers of this study go on to mention that “the critical relationship of fruit and vegetable intake and cancer prevention has been thoroughly documented. It has been suggested that major public health benefits could be achieved by substantially increasing consumption of these foods.”
* Here’s a very interesting fact for wine drinkers: “Moderate wine drinkers also seem to have a lower risk to develop cancer of the lung, endometrium, esophagus, stomach, and colon.”
Thank you flavonoids!
One study even mentioned that “fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine”!
We also read a study that recruited 1522 breast cancer cases and 1547 frequency control subjects from June 2007 to July 2018 in Guangdong, China. The results of this study indicated that consumption of “flavonoids and most flavonoid subclasses intakes were inversely associated with breast cancer risk.”
Finally, “the critical relationship of fruit and vegetable intake and cancer prevention has been thoroughly documented. It has been suggested that major public health benefits could be achieved by substantially increasing consumption of these foods.”
In other words... oxidation in our body leads to cancer and other diseases, therefore we should consume lots of antioxidants to stay healthy.
Learn all about Palo Azul's antioxidant property here
This is why it's so important to eat vegetables, fruit and drink Palo Azul tea every day! (or wine occasionally)
Here we have summarized the key points of the studies we reviewed and also cited them.
Enjoy! :)
...And don't forget to help your friends and family by sharing MagickTea Palo Azul with them!
Key findings from medical studies
• “Epidemiological studies suggest dietary intake of flavonoids may reduce the risk of tumors of the breast, colon, lung, prostate, and pancreas.”
• The following is the possible mechanism of flavonoids in cancer prevention: “Flavonoids have complementary and overlapping mechanisms of action including antioxidant activity and scavenging free radicals, modulation of carcinogen metabolism, regulation of gene expression on oncogenes and tumour-suppressor genes in cell proliferation and differentiation, induction of cell cycle arrest and apoptosis, modulation of enzyme activities in detoxification, oxidation and reduction, anti-inflammatory properties and action on other possible targets.”
• “Dietary flavonoids critically influence several cellular and immune processes associated with the development and progression of cancer. It is clear that these food components possess the propensity to modulate a variety of biological events associated with cancer progression and development, such as cell proliferation, apoptosis, cell differentiation and neovascularization."
• Epidemiological, clinical and animal studies reveal that “flavonoids may exert protective effects against various disease conditions including cardiovascular disease and cancer.”
• “Flavonoids have favourable biochemical and antioxidant effects associated with various diseases such as cancer, Alzheimer's disease (AD), atherosclerosis, etc.
• “The oxidative stress may lead to cellular damage which is related to various health ailments such as diabetes, cancer, CVD, neurodegenerative disorders and ageing.”
• “Flavonoids are important phytochemical components of wheat bran, and have been shown to be potent antioxidants with anticancer activity.“
“Flavones and isoflavones may play a prominent role in cancer prevention since these compounds are found in numerous plants that are associated with reduced cancer rates.”
• “Dietary flavonoids critically influence several cellular and immune processes associated with the development and progression of cancer. It is clear that these food components possess the propensity to modulate a variety of biological events associated with cancer progression and development, such as cell proliferation, apoptosis, cell differentiation and neovascularization.”
Medical Studies
* Palo Azul is commonly referred to by its scientific name: Eysenhardtia polystachya / E. polystachya / E.P - Cyclolepis genistoides / C. genistoides - kidney wood - palo dulce
(2009) Chapter 18 - Flavonoids and Cardiovascular Health
More than 8000 compounds with flavonoids structure have been identified, many of which are responsible for the attractive colors of flowers, fruits and leaves. In plants, these compounds afford protection against ultraviolet radiation, pathogens, and herbivores [1, 2].
Studies have indicated the protective effects of flavonoids in cardiovascular diseases and these chemicals possess the bioactivity to positively affect against cardiovascular risk factors such as lipoprotein oxidation, dyslipidemia and endothelial dysfunction. Flavonoids have strong antioxidant properties and so can reduce oxidative stress related to cardiovascular disease. The cardioprotective role of tea is reported to be due to antioxidant effect of the flavonoids, which act as scavengers for free radicals.
Epidemiological, clinical and animal studies reveal that flavonoids may exert protective effects against various disease conditions including cardiovascular disease and cancer. Flavonoids also possess antibacterial, antiviral, and anti-inflammatory effects. Population studies have shown that flavonoid intake is inversely correlated with mortality from cardiovascular disease [3–6]. Flavonoids have been reported to beneficially impact parameters associated with atherosclerosis, including lipoprotein oxidation, blood platelet aggregation, and vascular reactivity. Antioxidant, antithrombotic, anti-inflammatory, and hypolipidemic properties are illustrated to play a significant role in the lower cardiovascular mortality observed with higher flavonoid intake [4, 5, 7]. Continued studies of the mechanisms underlying the biological effects of plant flavonoids may provide new strategies for the prevention and treatment of cardiovascular disease.
(2016, Dec 29) (Medical Review: 161 studies) Flavonoids: an overview
Flavonoids, a group of natural substances with variable phenolic structures, are found in fruits, vegetables, grains, bark, roots, stems, flowers, tea and wine. These natural products are well known for their beneficial effects on health and efforts are being made to isolate the ingredients so called flavonoids. Flavonoids are now considered as an indispensable component in a variety of nutraceutical, pharmaceutical, medicinal and cosmetic applications. This is attributed to their anti-oxidative, anti-inflammatory, anti-mutagenic and anti-carcinogenic properties coupled with their capacity to modulate key cellular enzyme function. Research on flavonoids received an added impulse with the discovery of the low cardiovascular mortality rate and also prevention of CHD.
The recent studies on different plant metabolites have shown that flavonoids may perform a key role in enzyme and receptor systems of the brain, exerting significant effects on the central nervous system, like prevention of the neurodegeneration associated with AD and Parkinson's disease(,15,119).
They have miscellaneous favourable biochemical and antioxidant effects associated with various diseases such as cancer, Alzheimer's disease (AD), atherosclerosis, etc. Flavonoids have several subgroups, which include chalcones, flavones, flavonols and isoflavones. These subgroups have unique major sources. For example, onions and tea are major dietary sources of flavonols and flavones. A number of flavonoids were studied to lower Alzheimer's Aβ production using molecular docking studies.
Lee et al.(,81), while working on the known flavonoid inhibitors of β-KAS III against the methicillin-resistant bacteria Staphylococcus aureus, found that flavonoids such as naringenin (5,7,4′-trihydroxyflavanone) and eriodictyol (5,7,3′,4′-tetrahydroxyflavanone) are potent antimicrobial inhibitors of Staphylococcus aureus KAS III. Ganugapati et al.(,82) worked on in silico modelling and docking studies of a superbug enzyme, namely New Delhi metallo-β-lactamase-1 (NDM-1), which is an enzyme found in Escherichia coli.
Lu & Chong(,85) carried out the computational work to predict the binding modes of flavonoid derivatives with the neuraminidase of the 2009 haemagglutinin 1 neuraminidase (H1N1) influenza virus. They employed molecular dynamics simulation techniques to optimise the 2009 H1N1 influenza neuraminidase X-ray crystal structure. All the twenty flavonoid derivatives were found to be satisfactory in binding and inhibiting the activity of the virus. These findings may help to develop a potential drug form of the flavonoid derivatives for the treatment of H1N1 influenza disease.
Kim et al.(,87) reported that a flavonoid-rich diet is associated with a reduced risk of CVD (cardiovascular disease). The study focused on individual as well as total flavonoid diet effects. Higher flavonoid intake was found to be associated with the improved CVD risk factors.
The observational studies done by Hügel et al.(,89) indicated that dietary flavonoids are associated with a decreased risk of hypertension and CVD. A diet rich in all flavonoid classes through herbs and beverages improves vascular health leading to a reduced risk of diseases. It has been observed that the consumption of them is associated with improvement in endothelial function via vascular endothelial nitric oxide synthase and protein kinase B (Akt) activation. The effect of regular quercitin intake on blood pressure in overweight and obese patients with pre-hypertension and stage I hypertension was studied in seventy patients. Ambulatory blood pressure and office blood pressure were measured. It was observed that the blood pressure level was reduced in patients with hypertension(,90).
Paris et al.(,97) worked on flavonoids which lower Alzheimer's amyloid protein (Aβ) production via a nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB)-dependent mechanism. It is well known that AD is due to the accumulation of Aβ peptides and the presence of neurofibrillary tangles in the brain(,98,99). Aβ is believed to play an important role in AD and it has been shown that certain flavonoids such as genistein, quercetin, taxifolin, kaemferol, luteolin, apigenin, daidzein, aminogeneistein, and α- and β-napthofalvone can affect Aβ production. Recently, it was suggested that the Aβ-lowering properties of flavonoids are mediated by a direct inhibition of β active site cleavage enzyme-1 (BACE-1) activity, the rate-limiting enzyme responsible for the production of Aβ peptides(,97). It has been reported that a strong correlation exists between the inhibition of NF-κB activation by flavonoids and their Aβ-lowering properties, suggesting that flavonoids inhibit Aβ production in whole cells via NF-κB-related mechanisms.
Flavonoids can prevent injury caused by free radicals in various ways and one way is the direct scavenging of free radicals. Flavonoids are oxidised by radicals, resulting in a more stable, less-reactive radical. In other words, flavonoids stabilise the reactive oxygen species by reacting with the reactive compound of the radical. Because of the high reactivity of the hydroxyl group of the flavonoids, radicals are made inactive, as explained in the following equation as given by Korkina & Afanasev(,108): They further mentioned that this action protects the LDL particles and, theoretically, flavonoids may have preventive action against atherosclerosis.
Antioxidants are compounds that protect the cells against the oxidative effect of reactive oxygen species, and the impaired balance between these reactive oxygen species and antioxidants results in oxidative stress. The oxidative stress may lead to cellular damage which is related to various health ailments such as diabetes, cancer, CVD, neurodegenerative disorders and ageing. Oxidative stress can also damage many biological molecules and proteins and DNA molecules are significant targets of cellular injury. Antioxidants interfere with radical-producing systems and increase the function of endogenous antioxidants, protecting the cells from damage by these free radicals
Anticancer effects of flavonoids such as tangeritin, 3-hydroxyflavone, 3′,4′-dihydroxyflavone, 2′,3′-dihydroxyflavone, fisetin, apigenin, luteolin daidzein and genistein have been carried out by a number of researchers(,151–154). Ren et al.(,130) and Huang et al.(,155), while working on natural phenolic compounds and their potential use for cancer prevention, reported that various flavonoids such as tannins, stilbenes, curcuminoids, coumarins, lignans, quinones and other flavonoids have chemopreventive properties and also contribute to induce apoptosis by arresting the cell cycle, regulating carcinogen metabolism and ontogenesis expression. While explaining the possible mechanism of flavonoids in cancer prevention they further mentioned that the flavonoids have complementary and overlapping mechanisms of action including antioxidant activity and scavenging free radicals, modulation of carcinogen metabolism, regulation of gene expression on oncogenes and tumour-suppressor genes in cell proliferation and differentiation, induction of cell cycle arrest and apoptosis, modulation of enzyme activities in detoxification, oxidation and reduction, anti-inflammatory properties and action on other possible targets.
Flavonoids have also been recognised for their antimicrobial activity and many researchers have isolated and identified the structures of flavonoids having properties of antifungal, antiviral and antibacterial activity. Because of this property, many flavonoids are now being used extensively in the fields of nutrition, food safety and health. The antiviral effect of flavonoids has been shown by Wang et al.(,142), particularly in therapy for viral infection.
Flavonoids, like flavonols, are associated with lower population rates of dementia(,156). Similarly, Hwang & Yen(,157) and Jager & Saaby(,119) suggested that citrus flavanones such as hesperidin, hesperetin and naringenin could traverse the blood–brain barrier and may play an effective role in the intervention for neurodegenerative diseases. The role of flavonoids in antidiabetic activity and anti-ageing has also been reported(,158–161).
Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine.
Many flavonoids are shown to have antioxidative activity, free radical scavenging capacity, coronary heart disease prevention, hepatoprotective, anti-inflammatory, and anticancer activities, while some flavonoids exhibit potential antiviral activities. In plant systems, flavonoids help in combating oxidative stress and act as growth regulators.
The number of studies has suggested protective effects of flavonoids against many infectious (bacterial and viral diseases) and degenerative diseases such as cardiovascular diseases, cancers, and other age-related diseases. Flavonoids also act as a secondary antioxidant defense system in plant tissues exposed to different abiotic and biotic stresses.
Flavonoids found in the highest amounts in the human diet include the soy isoflavones, flavonols, and the flavones.
Oxidative modification of LDL cholesterol is thought to play a key role during atherosclerosis. The isoflavan glabridin, a major polyphenolic compound found in Glycyrrhiza glabra (Fabaceae), inhibits LDL oxidation via a mechanism involving scavenging of free radicals [52]. Several epidemiological studies have suggested that drinking either green or black tea may lower blood cholesterol concentrations and blood pressure, thereby providing some protection against cardiovascular disease. Flavonoids contained in berries may have a positive effect against Parkinson's disease and may help to improve memory in elderly people. Antihypertensive effect has been observed in total flavonoid fraction of Astragalus complanatus in hypertensive rats [55]. Intake of antioxidant flavonoids has been inversely related to the risk of incidence of dementia.
Flavonoids possess many biochemical properties, but the best described property of almost every group of flavonoids is their capacity to act as antioxidants. The antioxidant activity of flavonoids depends upon the arrangement of functional groups about the nuclear structure. The configuration, substitution, and total number of hydroxyl groups substantially influence several mechanisms of antioxidant activity such as radical scavenging and metal ion chelation ability
Hepatoprotective activities were observed in flavonoids isolated from Laggera alata against carbon-tetrachloride (CCl4-) induced injury in primary cultured neonatal rat hepatocytes and in rats with hepatic damage. Several clinical investigations have shown the efficacy and safety of flavonoids in the treatment of hepatobiliary dysfunction and digestive complaints, such as sensation of fullness, loss of appetite, nausea, and abdominal pain.
Flavonoids are known to be synthesized by plants in response to microbial infection; thus it should not be surprising that they have been found in vitro to be effective antimicrobial substances against a wide array of microorganisms. Flavonoid rich plant extracts from different species have been reported to possess antibacterial activity [70, 72, 89, 90]. Several flavonoids including apigenin, galangin, flavone and flavonol glycosides, isoflavones, flavanones, and chalcones have been shown to possess potent antibacterial activity [91]. These compounds are reported for their in vitro antibacterial activity against Vibrio cholerae, Streptococcus mutans, Shigella, and other bacteria [94, 95]. Another study demonstrated inhibitory activity of quercetin, apigenin, and 3,6,7,3′,4′-pentahydroxyflavone against Escherichia coli DNA gyrase [98].
Inflammation is a normal biological process in response to tissue injury, microbial pathogen infection, and chemical irritation. Inflammation is initiated by migration of immune cells from blood vessels and release of mediators at the site of damage. This process is followed by recruitment of inflammatory cells, release of ROS, RNS, and proinflammatory cytokines to eliminate foreign pathogens, and repairing injured tissues. In general, normal inflammation is rapid and self-limiting, but aberrant resolution and prolonged inflammation cause various chronic disorders [106]. A number of flavonoids such as hesperidin, apigenin, luteolin, and quercetin are reported to possess anti-inflammatory and analgesic effects. It has been reported that flavonoids are able to inhibit expression of isoforms of inducible nitric oxide synthase, cyclooxygenase, and lipooxygenase, which are responsible for the production of a great amount of nitric oxide, prostanoids, leukotrienes, and other mediators of the inflammatory process such as cytokines, chemokines, or adhesion molecules [110]. Much of the anti-inflammatory effect of flavonoid is on the biosynthesis of protein cytokines that mediate adhesion of circulating leukocytes to sites of injury. Certain flavonoids are potent inhibitors of the production of prostaglandins, a group of powerful proinflammatory signaling molecules [111].’
Dietary factors play an important role in the prevention of cancers. Fruits and vegetables having flavonoids have been reported as cancer chemopreventive agents [72, 115]. Consumption of onions and/or apples, two major sources of the flavonol quercetin, is inversely associated with the incidence of cancer of the prostate, lung, stomach, and breast. In addition, moderate wine drinkers also seem to have a lower risk to develop cancer of the lung, endometrium, esophagus, stomach, and colon [116]. The critical relationship of fruit and vegetable intake and cancer prevention has been thoroughly documented. It has been suggested that major public health benefits could be achieved by substantially increasing consumption of these foods [117]. Flavonoids are known to inhibit production of heat shock proteins in several malignant cell lines, including breast cancer, leukemia, and colon cancer [119].
Higher consumption of phytoestrogens, including isoflavones and other flavonoids, has been shown to provide protection against prostate cancer risk [132]. It is well known that due to oxidative stress cancer initiation may take place and thus potent antioxidants show potential to combat progression of carcinogenesis. Potential of antioxidant as an anticancer agent depends on its competence as an oxygen radical inactivator and inhibitor [70, 72, 133]. Therefore diets rich in radical scavengers would diminish the cancer-promoting action of some radicals [134].
Natural compounds are an important source for the discovery and the development of novel antiviral drugs because of their availability and expected low side effects. Naturally occurring flavonoids with antiviral activity have been recognized since the 1940s and many reports on the antiviral activity of various flavonoids are available. Many flavonoids, namely, dihydroquercetin, dihydrofisetin, leucocyanidin, pelargonidin chloride, and catechin, show activity against several types of virus including HSV, respiratory syncytial virus, polio virus and Sindbis virus [135]. Inhibition of viral polymerase and binding of viral nucleic acid or viral capsid proteins have been proposed as antiviral mechanisms of action [139].
Flavonoids have long been reported as serving multiple functions in plants [140]. Various abiotic and biotic factors helps in the generation of ROS in plants leading to oxidative stress. Flavonoids have been suggested as representing a secondary antioxidant defense system in plant tissues exposed to different stresses [141].
Prevention and cure of diseases using phytochemicals especially flavonoids are well known. Fruits and vegetables are natural sources of flavonoids. Variety of flavonoids found in the nature possesses their own physical, chemical, and physiological properties. Structure function relationship of flavonoids is epitome of major biological activities. Medicinal efficacy of many flavonoids as antibacterial, hepatoprotective, anti-inflammatory, anticancer, and antiviral agents is well established. Further achievements will provide newer insights and will certainly lead to a new era of flavonoid based pharmaceutical agents for the treatment of many infectious and degenerative diseases.
The healthy properties of flavonoids may be derived from their antioxidative characteristics as free-radical neutralizers. However, some more specific functions have been reported, including their effect on cancer prevention, antiinflammatory and antiviral activities, and their positive effect on capillary fragility and vascular protection.
The electrophilic properties of flavonoid quinones make them very reactive towards thiols in protein Cys residues to form cysteinyl flavonoid adducts, which may to a large extent explain their anti-inflammatory and anticancer effects among others.
A series of exogenous compounds (flavonoids) are able to protect against oxidative stress by induction of phase 2 enzymes (cytoprotective proteins) through activation of the redox sensitive Keap1-Nrf2-ARE regulatory pathway. Inducers of cytoprotective proteins are, for example, found among polyphenols of which many are present in our daily diet.
Polyphenols are direct antioxidants in vitro, but nevertheless seem to exert their antioxidant effect more by induction of cytoprotective proteins that are involved in a variety of antioxidant actions from reduction of oxidants to the production of endogenous direct antioxidants (e.g., glutathione). Therefore the protection against oxidative stress of polyphenols in vivo is mainly due to their indirect antioxidant effect.
(2014) Polyphenols in Chronic Diseases and their Mechanisms of Action
Dietary flavonoids play an important role in the prevention of diseases related to oxidative stress in living systems.
Numerous epidemiological studies show an inverse correlation between dietary flavonoid consumption and chronic degenerative diseases, such as cardiovascular diseases, diabetes, osteoporosis, neurodegenerative diseases, and cancers.
(2014) Antioxidant Properties of Wheat Bran against Oxidative Stress
Because of the high reactivity of the hydroxyl group, flavonoids (Fl-OH) are able to reduce highly oxidizing free radicals with redox potentials by hydrogen atom donation, according to Eq. (10), where R• represents superoxide anion, peroxyl, alkoxyl, and hydroxyl radicals.
Flavonoids are important phytochemical components of wheat bran, and have been shown to be potent antioxidants with anticancer activity.81,82 In addition, flavonoids have a role in the treatment of diabetes83,84 by virtue of their ability to protect against hyperglycemic and alloxan-induced oxidative stress in experimental animal models.85 In a large cohort of women, a clinical trial has shown that flavonoids are protective against type 2 diabetes.
These components of wheat bran possess health benefits for humans, including preventative effects against cancer and type 2 diabetes. Various studies have reported that these compounds exhibit significant antioxidant capabilities, including scavenging free radicals, chelating metal ions, and activating antioxidant enzymes, suggesting antioxidant properties of wheat bran. This chapter includes an overview of stress and oxidative stress and a discussion of the antioxidant properties of wheat bran.
(2014) Chapter 32 - Anti-Inflammatory and Immunomodulatory Properties of Dietary Flavonoids
Flavonoids are the most common group of polyphenolic compounds in the human diet and are found ubiquitously in fruits, vegetables, nuts and plant-derived beverages, such as tea and wine. These compounds have been reported to possess a wide range of activities in the prevention of common diseases, including coronary heart disease, cancer, neurodegenerative diseases, gastrointestinal disorders, and others.
Their beneficial effects appear to be related to the various biological/pharmacological activities of flavonoids. A large body of research suggests immunomodulatory and anti-inflammatory properties of these compounds.
Flavonoids may be important for the overall therapeutic effect of THC and the other cannabinoids by either synergistically enhancing them or reducing their side effects.224 Flavonoids may counteract some unwanted effects caused by THC, such as the upregulation of tumor necrosis factor-alpha (TNF-α).
Prenylated flavonoids are attracting increasing attention from the scientific community because of their potent antioxidant and anticancer effects, and their potential for treating menopausal problems.270
(2012) Flavonoids and cancer prevention: a review of the evidence.
Epidemiological studies suggest dietary intake of flavonoids may reduce the risk of tumors of the breast, colon, lung, prostate, and pancreas.
A limited number of intervention trials of flavonoids have documented cancer preventative effects. Proposed anticancer mechanisms for flavonoids are inhibition of proliferation, inflammation, invasion, metastasis, and activation of apoptosis. Prospective studies with larger sample sizes are needed to develop biomarkers of flavonoid intake and effect.
(2001) Dietary agents in cancer prevention: flavonoids and isoflavonoids.
Flavones and isoflavones may play a prominent role in cancer prevention since these compounds are found in numerous plants that are associated with reduced cancer rates. Many mechanisms of action have been identified for isoflavone/flavone prevention of cancer, including estrogenic/antiestrogenic activity, antiproliferation, induction of cell-cycle arrest and apoptosis, prevention of oxidation, induction of detoxification enzymes, regulation of the host immune system, and changes in cellular signaling.
It is expected that some combination of these mechanisms will be found to be responsible for cancer prevention by these compounds. Compelling data suggest that flavones and isoflavones contribute to cancer prevention; however, further investigations will be required to clarify the nature of the impact and interactions between these bioactive constituents and other dietary components.
(2005) The antitumor activities of flavonoids.
An impressive body of information exists on the antitumor action of plant flavonoids. In vitro work has concentrated on the direct and indirect actions of flavonoids on tumor cells, and has found a variety of anticancer effects such as cell growth and kinase activity inhibition, apoptosis induction, suppression of the secretion of matrix metalloproteinases and of tumor invasive behavior.
Experimental animal studies indicate that certain dietary flavonoids possess antitumor activity. The hydroxylation pattern of the B ring of the flavones and flavonols, such as luteolin and quercetin, seems to critically influence their activities, especially the inhibition of protein kinase activity and antiproliferation.
Dietary flavonoids critically influence several cellular and immune processes associated with the development and progression of cancer. It is clear that these food components possess the propensity to modulate a variety of biological events associated with cancer progression and development, such as cell proliferation, apoptosis, cell differentiation and neovascularization.
Certain dietary flavonoids display in vivo antitumor activity and depress in vivo angiogenesis.
Results: A total of 12 studies (5 cohort and 7 case-control studies) involving 17,481 cases and 740,859 controls were eligible for meta-analysis. High intake of dietary flavonols, flavones and anthocyanidins may decrease the risk of colorectal cancer;
Conclusions: The present study suggested that high intake of flavonols (such as quercetin) may reduce the risk of colon cancer, and high intake of flavones (such as apigenin) may reduce the risk of rectal cancer.
This case-control study recruited 1522 eligible breast cancer cases and 1547 frequency-matched control subjects from June 2007 to July 2018 in Guangdong, China.
After adjusting for potential confounders, inverse associations were observed between total flavonoids, anthocyanidins, proanthocyanidins, flavanones, flavones, flavonols and isoflavones and overall breast cancer risk.
This study indicates that total flavonoids and most flavonoid subclasses intakes were inversely associated with breast cancer risk.
(2019) Flavonoids and bladder cancer risk.
We analyzed data from an Italian case-control study including 690 incident bladder cancer cases and 665 controls admitted to the same network of hospitals for acute, non-neoplastic, non tobacco-related diseases.
We found an inverse association between isoflavones (OR for the highest compared to the lowest quintile of intake = 0.56, 95% CI 0.37-0.84) and flavones (OR = 0.64, 95% CI 0.44-0.95) and bladder cancer. Non-significant inverse association was found for flavan-3-ols (OR = 0.70), flavonols (OR = 0.85) and total flavonoids (OR = 0.76)
Our data indicate an inverse association between isoflavones and flavones with respect to bladder cancer risk.
So, what are you waiting for?