Life Extension Magazine April 2012
Apple Polyphenols and Longevity
By George Randall
Apple Polyphenols Prevent Colon Cancer by Multiple Mechanisms
Colorectal cancer is the second leading cause of cancer-related deaths in the United States and the third most common cancer in men and in women.38 Apple polyphenols reach the colon in large concentrations, and they show great promise in reducing the burden of this common disease.39 Indeed, large-scale epidemiological studies show that those who consume larger amounts of apple polyphenols can cut their colon cancer risk by nearly 50%.40
Apple polyphenols act by multiple mechanisms against multiple targets in the toxic environment of the colon. They reduce the substantial oxidant stress under which colon cells must survive, and they scavenge oxygen free radicals, a potent means of reducing cellular and DNA damage.41-43 They also enhance production of natural antioxidant enzymes that colon cells use to protect themselves.44-47
Inflammation typically follows oxidant damage, and is a key event in promoting colon cancer. Apple polyphenols inhibit enzyme systems known as cyclooxygenase and lipoxygenase, both of which produce inflammatory cytokines.41,43,48-51 Apple polyphenols also enhance the rate at which your normal colonic bacteria produce the anti-inflammatory molecule butyrate from dangerous long-chain fats.27,52,53 Butyrate is natural protective element against colon cancer and inflammatory bowel disease.54,55
Many colon cancers are triggered by ingestion of carcinogens in the diet; apple polyphenols promote expression and activity of a range of vital detoxification enzyme systems.45,56 Those systems are essential in preventing carcinogenic chemicals from further damaging cells.
Oxidation, inflammation, and toxins all ultimately produce damage to DNA, which is a first step in formation of cancerous cells. Apple polyphenols show powerful protection of colon cells’ DNA.46,57
Even once a cancer has formed, animal studies have shown that apple polyphenols can slow or stop its growth through several mechanisms. They block the chemical receptors for a molecule called epidermal growth factor, needed by tumor cells to continue their development.58 Apple polyphenols have also been shown to reactivate tumor suppressor genes that have been switched off in cancerous cells, restoring their ability to regulate their growth safely.59 And they induce the cellular suicide mechanism called apoptosis, which is also often switched off in tumor tissues.60,61
The end result of all these actions is to reduce the out-of-control growth typical of cancerous tissue.42 In the lining of the colon, where tumors begin, this is manifested by a reduction of up to 50% in so-called aberrant crypt foci, the pre-cancerous lesions often found on colonoscopy.48,62 And apple polyphenols reduce the numbers of actual pre-cancerous polyps by up to 42% and their growth rate by as much as 60% in animal models.63
Apple Polyphenols Lower Blood Glucose, Prevent Glycation Damage
Even very small blood sugar elevations, especially those immediately following a meal, are now known to be a major cause of tissue damage, even in those who are not diabetic.64 Glucose, though a vital fuel for life, has substantial toxic effects on your body’s proteins over the long haul, producing damaging advanced glycation endproducts (AGEs). Once again, apple polyphenols can help.
Apple polyphenols, especially the unique molecule phloridzin, prevent uptake of glucose from the intestinal tract.15, 65 They do this by inhibiting certain specific glucose transport molecules in the intestinal lining.15,65-68 Animal studies demonstrate significant reductions in overall blood sugar levels.13,64,69 One such study also showed that apple polyphenols completely abolished the after-meal surge of blood sugar levels that’s known to be so dangerous.70
Apple polyphenols also act to block the formation of advanced glycation endproducts, protecting cells from their damaging effects and from the inflammation that can follow.19,75 Furthermore, apple polyphenols scavenge dangerous dicarbonyl molecules that promote glycation and accelerate aging.3,14
Most Life Extension members take nutrients like carnosine, benfotiamine, and pyridoxal-5-phosphate to inhibit deadly glycation reactions, but as already described in this article, apple polyphenols have unique beneficial properties that extend beyond their anti-glycation effects.
Apple Polyphenols Boost Immunity, Fight Infection
Infections are all too often the cause of an untimely death in older people, even in today’s world of antibiotics. Apple polyphenols are powerful natural antimicrobial agents, and are showing great promise in arresting some of the most threatening infections.
Apple polyphenols bind to toxins produced by the bacterium Staph aureus, inactivating them and preventing their deleterious effects.71 Those effects include deadly conditions such as toxic shock syndrome and massive food poisoning, which is common.72 The polyphenols are also active against other common bacterial infections such as Pseudomonas and Bacillus species, and against so-called “atypical” tuberculosis infections.73, 74
The bacterium Helicobacter pylori is the cause of gastritis and stomach ulcers. Apple polyphenols inhibit not only the organism’s growth, but also its ability to bind to stomach lining cells, and its ability to promote inflammation.75 These effects have the potential to prevent recurrence of the bacterial infection and its results after conventional medical treatment.
Of greatest interest is the recent discovery that apple polyphenols can protect animals infected with the deadly H1N1 influenza virus, a potential cause of death among elderly people. Stressed animals with the flu died much sooner than did control animals, but those treated with apple polyphenols survived at much higher rates and lived longer.76
Apples, and especially their skins, are among the fruits richest in the specialized molecules called polyphenols. Apple polyphenols, found in high quantities in the apple’s skin, exert powerful antioxidant, anti-inflammatory, and anti-glycation effects. Together, these effects combine to protect your body from many of the reversible consequences of aging. Compelling evidence exists for apple polyphenols’ ability to prevent, and even reverse changes that produce cardiovascular disease, cancer, elevated blood sugar, and even serious infections.
Since health conscious people today obtain a wide range of polyphenols (such as green tea and pomegranate extracts), a daily dose of 300 mg to 600 mg of apple polyphenols may be all that is needed to obtain desired benefits.
If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.
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