Super reds and super foods — Will more antioxidant flavonoid foods make us healthier?
Have you caught the red craze yet? Every weekend, local radio stations run hours of shows describing the miraculous health benefits of concentrated essences of nature’s most colorful fruits and vegetables. Super berries, red cherry concentrates, super reds, and super berry blends — there are countless products to choose from. Before the first “commercial” break — it’s unclear how you can have a commercial during a show that is a “paid commercial advertisement” but, perhaps they’re hoping you’ll forget it’s not a real show and that they’ve aired the same segment every weekend for the past year — you’re certain to be convinced that you if you’re not consuming vast amounts of flavonoids in your diet every day, then you’re not eating right and not doing everything you need to stay healthy.
These “superfoods,” part of the growing functional food movement, are said to contain plant chemicals, phytochemicals, called flavonoids. Purportedly, flavonoids have antioxidant and anti-inflammatory properties and can treat, prevent or cure practically anything that ails you — arthritis, gout, joint pain, heat disease, stroke, cancers, sleep problems, Alzheimers, Parkinson’s, cataracts, fibromyalgia, hypertension, diabetes, fatty liver, infections, aging, diminished cognitive function, varicose veins, headaches, hayfever, eczema, allergies, hemorrhoids, and, of course, obesity.
Not so fast.
What you probably haven’t heard is that the FDA issued a permanent injunction on Friday against cherry/berry companies making any health claims for their products. The companies, Brownwood Acres Foods Inc., Cherry Capital Services Inc. (doing business as Flavonoid Sciences) and top executives are prohibited from making or distributing any products (fruit products, juice concentrates, supplements or powders, glucosamine and fish oil capsules) claiming “to cure, treat, mitigate or prevent diseases.” “The FDA will not tolerate unsubstantiated health claims that may mislead consumers,” said the associate commissioner for regulatory affairs in the FDA news release. “The FDA will pursue necessary legal action to make sure companies and their executives manufacture and distribute safe, truthfully labeled products to consumers.” Brownwood Acres Foods, Inc. company’s website now only says its products have “Powerful Antioxidants - to attack your body’s harmful free radicals...known to be highly beneficial for optimal health.” Not only has the public heard little about this injunction, but fewer have heard that it occurred more than two years after the FDA issued its first warning letter, finding the company in violation of the Federal Food, Drug, and Cosmetic Act on October 17, 2005, for making unscientific and unproven medical claims. At that time, the company’s website said cherries have antioxidant power for “arthritis, gout, joint inflammation, cancer prevention, fibromyalgia syndrome and heart disease” and that “recent studies how the antioxidant compounds in cherries may be 10 times stronger than Aspirin or Ibuprofen in relieving arthritic pain.” Tart cherries contain perillyl alcohol which, they claimed, is “extremely powerful in reducing the incidences of all types of cancer...[and work] in the treatment of advanced carcinomas of the breast, prostate and ovary...[and] ellagic acid [in cherries] may be the most potent way to prevent cancer.” Wild blueberries were said to contain high levels of anthocyanins that may “help prevent heart disease and stroke, guard against Alzheimer's and other neurological diseases.” The website, according to the FDA, had included claims in the form of “testimonials,” such as being effective for joint pain and stiffness associated with osteoarthritis and other degenerative processes, fibromyalgia, rheumatoid arthritis and lupus, and urinary tract infections. This company was one of 29 companies that received Warning Letters from the FDA on October 17, 2005, for making nearly identical claims on their websites and product labels. Of those, as of today, all have complied but five, which are blatantly thumbing their noses at the FDA and violating its ruling by continuing to make medical claims for their products and supplements. As of yet, no FDA injunctions have been issued on those companies. Two companies took another tactic in response to the FDA warning letters. For medical claims, they now link their website visitors to the Cherry Marketing Institute website. This is a paid marketing company, funded by cherry growers and processors, with cooperative relationships with the American Heart Association, American Diabetic Association, American Dietetic Association, National Sleep Foundation, Arthritis Foundation, American Cancer Society, Mayo Clinic, and Cleveland Clinic. From this marketing group are found the most extreme claims, nearly verbatim to those that originally appeared on the FDA-cited websites. It also produces regular press releases for the media with claims for these super foods. This content has found its way into many of the papers and magazines consumers read. By going through these trade groups and health media companies, their spurious claims would appear untouchable by the FDA. Friday, the same day the FDA issued its injunction, Natural News was reporting that fruits rich in these chemicals — including blackberries, blueberries, strawberries, raspberries, sour cherries, pomegranates and cranberries — held special anti-inflammatory properties and that with simple diet changes alone, the inflammatory processes in “heart disease, stroke, Alzheimer's, cancers, arthritis, gingivitis and other "itis" disorders” could be ended. “Anti-oxidant properties in some foods also help fight inflammation by protecting the body from free radicals,” the author wrote. “Quercetin is a flavonoid, and a very powerful one. It is found in red grapes, red and yellow onions, garlic, broccoli and apples.” The current issue of AARP Magazine also gives members a list of “Superfoods... power-packed with nutrients that will help your body ward off infection.” Red and blue berries and tea made the list for their antioxidant flavonoids. Even WebMD includes berries and tea on its list of “superfoods everyone needs [to] help ward off heart disease, cancer, cholesterol, and more.” Purity Products, Inc., whose radio spots have been especially prolific, says its super red formula berry blend “supercharge[s] your body with superior antioxidant protection [that] powerfully support heart and cardiovascular health, healthy joints, healthy immunity, health vision, healthy energy levels” And its phytonutrient rich berry blend “support[s] optimal liver, immune, neurological, cardiovascular and eye functions...” The FDA cannot begin to keep up with the thousands of companies selling natural foods and supplements, claiming to offer some special healthful benefit. We have to understand a bit of science ourselves, or at least remember those basic adages: if something sounds too good to be true... and the dose makes the poison, just because a little of something might be beneficial doesn’t mean more is better. Flavonoids are polyphenolic compounds that are synthesized by plants. More than 4,000 different flavonoids have been identified and they are widespread in nature, many in fruits, vegetables and drinks made from them. They are among the numerous natural plant pesticides — array of chemicals plants produce to defend themselves against fungi, insects and other animal predators — that we eat everyday (1,500 mg/day/person). Flavonoids are categorized by their chemical structure — flavonols, flavones, flavanones, isoflavones, chalcones, catechins, anthocyanidins — with most (but the last two) bound to sugar molecules which is the form most reach the small intestine to be digested. Quercetin is the most abundant dietary flavonol, according to Dr. Cristobal Miranda, Ph.D., Assistant Professor, Senior Research Department of Pharmaceutical Sciences and Dr. Donald R. Buhler, Ph.D., Professor, Department of Environmental and Molecular Toxicology, both with the Linus Pauling Institute at Oregon State University. Perhaps not surprisingly given their function for plants, in a test tube (in vitro studies) flavonoids seem to have antiviral, anti-inflammatory, anti-tumor and antioxidant activities, which has sparked tremendous interest for their potential role in human health. To date, the only other evidence to suggest a possible role in human health has been epidemiology studies finding untenable associations. JFS readers are familiar with these studies that look for correlations and try to claim a causal link. Their main focus anymore seems to be to support marketing agendas and convince us that certain politically-correct foods are better than those some believe we’re not supposed to be eating. Take the benefits of tea, for instance, which is on all of those “superfood” lists for its antioxidant flavonoids. Researchers have taken a group of people, compared those consuming tea and those not, based on food frequency questionnaires, and found that tea drinking is inversely related to heart disease mortality. Since tea contains flavonoids, that must be the “reason,” failing to consider a zillion confounders such as genetics, socioeconomic and stress factors. Why did they pick tea? They could just as easily have chosen to look at beer, which Dr. Joe A. Vinson, Ph.D., from the University of Scranton in Pennsylvania, found contains flavonoids with higher antioxidant activity than green tea, red wine or grape juice. As Drs Miranda and Buhler pointed out in a recent Linus Pauling Institute article, the antioxidant activity of the flavonoids in hops and beer far exceeds that of red wine, tea or soy! Beer, however, doesn’t have the same feel good connotation associated with virtuous “healthy” eating. :) Another epidemiological association gave birth to the current red food fad. In explaining the “French paradox,” it was assumed it must be the red wine — not the genetics among this more homogenous population — to explain lower heart disease. Since wine’s red color comes from grape skins which contain antioxidants like flavonoids and resveratrol, that was assumed to be the “cause” for the correlation. And the red myth was off and running. The science is controversial, though, as studies have since found that any alcoholic beverage appears to confer heart benefits. There’s probably not much of a market for an alcohol supplement or for medicinal brandy, either. It just doesn’t have the same “healthy” connotation. While flavonoids have elicited tremendous interest for their potential antioxidant health benefits, the science turns out to be more complicated and a lot less conclusive. As researchers from the Vrije Universiteit Medical Center, Wageningen, Netherlands, found in a review of the possible mechanisms of action and potential health applications for flavonoids in the American Journal of Clinical Nutrition, most of the research on flavonoids has involved in vitro studies or occasional rodent studies, but the benefits are not being supported in clinical trials and studies on humans. The antioxidant effects seen in test tubes may not have much effect inside the body and the science cannot draw definite conclusions about the usefulness of flavonoids in the diet, they found. Of special caution: “Data on the long-term consequences of chronic flavonoid ingestion are especially scarce.” According to the Linus Pauling Institute: Flavonoids are effective scavengers of free radicals in the test tube (in vitro). However, even with very high flavonoid intakes, plasma and intracellular flavonoid concentrations in humans are likely to be 100-1,000 times lower than concentrations of other antioxidants, such as ascorbate (vitamin C) or glutathione. Moreover, most circulating flavonoids are actually flavonoid metabolites, some of which have lower antioxidant activity than the parent flavonoid. For these reasons, the relative contribution of dietary flavonoids to plasma and tissue antioxidant function in vivo is likely to be very small or negligible. Although various flavonoids have been found to inhibit the development of chemically-induced cancers in animal models of lung, oral, esophageal, stomach, colon, skin, prostate and mammary (breast) cancer, epidemiological studies do not provide convincing evidence that high intakes of dietary flavonoids are associated with substantial reductions in human cancer risk. Most prospective cohort studies that have assessed dietary flavonoid intake using food frequency questionnaires have not found flavonoid intake to be inversely associated with cancer risk. Two prospective cohort studies in Europe found no relationship between the risk of various cancers and dietary intakes of flavones and flavonols, catechins or tea ... In other words, beliefs that flavonoids hold super curative powers in our diet greatly overstate the science. There is no credible scientific evidence to believe any food or ingredient holds special powers to heal. People around the world have enjoyed a wide range of diets with no common relationship to lifespans or health. So, not surprisingly, every single primary prevention clinical trial of antioxidant supplementation or higher intakes of fruits and vegetables and “healthy eating” (for example here, here, here, here, here, here, here, here) has found no effect on heart disease, cancers or premature mortality. Not only can the science help us relax and return to the pleasures of the table, it can stop the blame and guilt imposed on those who get sick for having not eaten “healthy” or followed some chaste diet. The sales pitches of super reds, which concentrate as many different flavonoid-rich fruits and vegetables possible, want us to believe that our diets are deficient, our health is bad and that we need far more nutrients than we get in our diets. This belief isn’t based on good science, either, wrote Dr. William T. Jarvis, Ph.D., while professor of public health and preventive medicine at the Loma Linda University School of Medicine, in a 1983 issue Annual Review of Nutrition. “Magical thinking about food,” particularly the idea that certain foods, vitamins or nutrients can prevent or cure illness and maintain youthfulness, has given foods pharmacological properties in pop culture, he said. Sadly, magical food beliefs have changed little over subsequent decades. Overstating the science, advertising, and even the overemphasis on nutrition education has promoted food faddism and health fears, he said, leaving consumers turning to healthy foods in an “attempt to obtain ‘supernutrition’ or to avoid ‘depleted’ foods." Getting the small amounts of nutrients our bodies need actually isn’t hard to achieve by enjoying some variety of foods. Even the “emphasis on the ‘well-balanced diet’ also favors food faddism,” said Dr. Jarvis, who also founded the National Council Against Health Care Fraud. “A national study on health practices and beliefs conducted for the FDA found that 86% of the public believed ‘anyone who eats balanced meals can get enough vitamins in his regular food;’ yet the majority of the respondents still used or had used supplements because they didn’t think they ate ‘balanced’ meals. The words ‘well-balanced meal’ and ‘balanced diet’ apparently suggest that a healthful diet is a precarious achievement.” It’s not. The human species would never have survived to this point if we were that fragile. Actual nutritional deficiencies are rare in populations where food is available. The most common cause of poor nutrition isn’t eating “bad’ foods, but eating too few calories, restricting our diets or eliminating foods, according to Dr. Sidney M. Wolfe, M.D., author of Worst Pills, Best Pills. Rates of heart disease and cancers have been dropping for well over half a century, and life expectancies have increased, despite the modernization of the food supply and no change in fruit and vegetable consumption. American health has improved, not deteriorated, and nutritional-deficiency diseases have been nearly eradicated. There is no need to eat like food is medicine and that disease prevention is the sole reason for eating. But concerns with “healthy” eating and food fears can harm people, said Dr. Jarvis. And not just by costing more for special foods and supplements. Recommending the overuse and underuse or avoidance of certain nutrients has caused malnutrition and health problems. With anything, there can be too much or too little — water is essential for life but you can die from drinking too much. Flavonoids is another example of not just how our beliefs about foods often don’t make scientific sense, but why more isn't better. To illustrate how illogical our fears about foods and chemicals can be, many people fear any detectible amount in food of any chemical that has ever been shown to cause cancer in rodent studies. No one would argue, though, that fruits, vegetables, nuts and teas can’t be part of a healthful diet. Yet, quercetin is one of the flavonoids that’s been tested and found to be carcinogenic in rodent studies (which use high exposures), according to Dr. Bruce N. Ames, Ph.D., renowned researcher on mutagenic and carcinogenic risks and professor in Biochemistry & Molecular Biology at the University of California, Berkeley and Dr. Lois Swirsky Gold, Ph.D., director of the Carcinogenic Potency Project at University of California, Berkeley. But like all chemicals, natural or synthetic, they caution, the low levels of chemicals our bodies are naturally exposed to every day are highly unlikely to be a risk for cancer. “Humans have many natural defenses that buffer against ordinary exposure to toxins and these are usually general, rather than tailored for each specific chemical.” Researchers now understand that the antioxidant capacity of flavonoids is decreased when broken down by digestion; the body perceives them as foreign compounds and tries to excrete them rapidly. It also appears that it only takes small amounts to see healthful benefits, but more is not necessarily better. Just because certain foods are bursting with some nutrient that appears healthful does not mean that even more is very, very healthful. The logic used by those promoting antioxidants for anti-aging also reflects a misunderstanding of how cells detect and repair the damage caused by free radicals and the important role that free radicals play in normal physiological processes (such as the immune response and cell communication), according to anti-aging experts. While free radicals promote beneficial oxidation, in excess they produce harmful oxidation that can cause cell damage, doctors Stephen Barrett, M.D., and Victor Herbert, M.D., J.D., M.A.C.P., F.R.S.M. have explained. Vitamins C and E and beta-carotene, for example, are mischaracterized as ‘antioxidants,’ when they are really redox agents (antioxidants in some instances and pro-oxidants in others, producing harmful free radicals). That may explain why antioxidant supplements or eating more fruits and vegetables high in antioxidants have not proven out to be beneficial in clinical trials on real people, and in some cases suggest harmful effects. Dr. Martyn T. Smith, Ph.D., professor of toxicology at the University of California, Berkeley, has particularly cautioned about consuming high concentrations of flavonoids being sold as health food supplements. Writing in the journal, Free Radical Biology and Medicine, he and co-author Christine F. Skibolaa said that at low concentrations, flavonoids appear to acts as antioxidants and potentially have anti-cancer actions to block and inhibit cell division. But the amounts in some popular supplements they tested found levels 10 to 20 times what is recommended for the human body. “At high concentrations, certain flavonoids can act as pro-oxidants and become mutagenic, meaning that they could cause oxidative damage and cause DNA and chromosome damage,” they said. At these levels, flavonoids can also alter normal body functions, hormones, interfere with metabolism of drugs and interfere with the absorption of needed minerals. Women of childbearing age who might become pregnant should be especially careful, they wrote, as flavonoids cross the placenta. The fact is, high levels of flavonoid consumption has never been tested and shown to be safe in humans, and the potential adverse effects may outweigh benefits. “Just because something comes from a natural source doesn't mean it can't hurt you,” Skibola said. “The dose makes the poison....unfortunately people tend to forget that.” The FDA’s public announcements warn that companies claiming their foods and supplements act like drugs and can cure or treat various health conditions do not have scientific evidence behind them. Despite the Cherry Marketing Institute’s claim that “the higher the ORAC [Oxygen Radical Absorbance Capacity] score, the better a food is at helping our bodies fight diseases like cancer and heart disease,” there is no evidence that the more ORAC units we consume, the healthier we are. We do not have to start counting ORAC units or anything else to eat well, live well and be well. © 2008 Sandy Szwarc
What are flavonoids?
Too much of a good thing
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