Down with flavones, flavanols and flavanones; the hydroxycinnamates, hydroxybenzoates and all carotenoids! No, I do not mean that these and all the other antioxidants should be banned from our food supply where they play an essential role. But the term 鈥渁ntioxidant鈥� is used as a marketing tool far too often. Today, blueberry jam has become "...a source of anthocyanins, 100% natural antioxidants". We do not enjoy tomatoes anymore for their taste, but rather fulfill our requirements for lycopene; chocolate is consumed for its content in catechins and green tea for the presence of quercetin.
How did we get to that situation?
About twenty years ago scientists linked diseases such as cancer, cardiovascular diseases and diabetes to a class of destructive molecules called "free radicals". These molecules also known Reactive Oxygen Species (ROS), are the unavoidable results of respiration. Oxygen, essential to the metabolic reactions of life, also produces the highly-reactive free radicals. Factors, such as smoking, pollution and a deficient diet also promotes their formation. The characteristic feature of free radicals is the presence in their structure of a single electron. As it is, electrons love company, they normally occur in pairs. This is why the electron-deficient free radicals continuously attack molecules in the body, including our DNA, to "rob" them of their electrons. Today, the scientific consensus is that the attacks, which are based on an "oxidation" process, are the root cause of a number of degenerative diseases.
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Natural defence
However nature offers us tools to fight off free radicals. Numerous epidemiological studies have shown that a diet rich in fruits and vegetables reduces the risks of developing a variety of degenerative diseases. The explanation is that these foods contain molecules, the famous "antioxidants", capable of neutralizing the free radicals. Because of their structure antioxidants can give their missing electron to the free radicals without they them themselves initiating destructive processes. Plants make antioxidants to protect themselves from the oxygen produced as part of photosynthesis but also as natural pesticides to fend off their predators. The discovery of the role played by antioxidants in battling free radicals led to an explosion in the market for nutritional supplements with sales reaching billions a year in North America. For a time it was the antioxidant vitamins 鈥� vitamin C, vitamin E, vitamin A and its precursor beta carotene 鈥� that led the pack. However the fad did not last when it was realized that more of a good thing is not better. Not only did antioxidants supplements not bring any benefits but, in the case of beta carotene for example, aggravated pre-existing health conditions. Since then promoters have moved to the marketing of food based on their antioxidant content. Tea marketers tell us that green tea is a source of epigallocatechin, a potent anti- oxidant that prevents cancer. To what chocolate importers reply that the epicatechin in chocolate is a more potent anti-oxidant than the epigallocatechin in green tea. In addition we are bombarded by claims made by distributors of exotic fruit juices, all supposedly with high antioxidant content. The gamut goes from the Tahitian noni to the Brazilian a莽ai or the Asian pomegranate. And it is a booming market. One of the companies that distributes mangosteen juice, a fruit originating in South-East Asia recently declared yearly profits of 500 million dollars.
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Food or drugs?
The more we learn about the properties of antioxidants the more we realize that it is not the singling of an isolated antioxidant-rich food that will protect us from disease. A proper evaluation requires an understanding of the jargon used by the marketers. Promoters for instance claim that their product has the highest "ORAC" values. Is it meaningful? The ORAC laboratory test, from Oxygen Radical Absorbance Capacity, measures the degradation of fluorescent molecules by free radicals in the presence of various antioxidants. The level of protection antioxidant are supposed to provide is derived from the decrease in fluorescent luminosity as a function of time. However often the values advertised by the promoters do not specify if these are for grams, calories or food portions. More importantly though one must realize that the body is not a test tube and results obtained in the lab may not apply to humans. There antioxidants face a variety of molecules with a myriad of possible competing reactions. A healthy and balanced diet is essential. This does not however require that we treat our food as drugs. The two major health risk factors in North America are smoking and obesity. We may drink as much mangosteen juice as we want, this will not extend our life expectancy if we do not deal with these problems. One should eat fruits and vegetables, not because of the presence of one or another antioxidant in particular, but because we know that it is the combination of all the molecules they contain that are of benefit to health. And we should not forget that eating should a pleasure. Let us take the time to enjoy our food. The French have a very low incidence of heart disease. This despite a diet high in saturated fats which comes in part from their high consumption of butter and of course the 246 varieties of cheese that is the pride of the country1 For some the explanation, for the so-called "French Paradox", is the presence in wine of resveratrol, an antioxidant molecule. But for me the "French secret" is more likely due to the fact that meals in France are still privileged moments when food is appreciated for its taste and not for its chemical composition. The glass of wine that accompanies the meal sends a signal to the brain to start the process and take the time to derive the best of what food has to offer. And it is why at the beginning of a meal the glass of wine is raised ...to health! 1 From the famous quote by Charles de Gaulle: "How do you want to govern a country with 246 varieties of cheese"!
