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Antioxidants
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Antioxidants are molecules that prevent cell damage and serve as parts of enzymes. There are many types of antioxidants found in nature.[4] Antioxidants are molecules that can counteract the damaging effects of oxygen in tissues and other materials. So far, the new antioxidants have been tested “in vitro” – in the test tube. Antioxidants are said to protect our cells from harmful substances called free radicals which are what create damage leading to many chronic diseases. However, scientists say that there is more to learn about the health benefits of antioxidants. Antioxidants are found in fruits, vegetables, herbs including many teas. It is the typical American diet that very much lacks sufficient amount of antioxidants.[7] Antioxidants are being widely used in routine general clinical practice. An increased interest in the role of free radical oxidative damage in human diseases along with an upsurge in research implies its potential in dental practice too.[8] Antioxidants are thought to protect the body's cells from the damaging effects of molecules called free radicals. Many researchers believe that free radicals damage the body's tissues.[9]
Antioxidants are substances that inhibit the rate of oxidation caused by free radicals. Antioxidants can be classified in five major groups based upon where and how they work within the body.[10] Antioxidants are needed to prevent the formation and oppose the actions of reactive oxygen and nitrogen species, which are generated in vivo and cause damage to DNA, lipids, proteins, and other biomolecules. Endogenous antioxidant defenses (superoxide dismutases, H2O2-removing enzymes, metal binding proteins) are inadequate to prevent damage completely, so diet-derived antioxidants are important in maintaining health.[11] Antioxidants are powerful protectors. These substances, found in everyday foods, can thwart reactions of free radicals that wreak havoc in the body.[12] Antioxidants are highly abundant in fruits and vegetables (ascorbate or vitamin C, carotenoids and polyphenols), nuts and grains (tocopherols and tocotrienols collectively called vitamin E), meat and dairy (vitamin A), and seafood (selenium). Beta carotene (red, yellow-orange and leafy green vegetables and fruits), lutein (green leafy vegetables), and lycopene (tomatoes) are other well-known antioxidants. Antioxidants are present in many foods, most famously in berries, certain vegetables, red wine, green tea and even dark chocolate, and are also beneficial when taken as supplements. One of the great things about antioxidants is that they are not drugs or pharmaceuticals - they are essential and naturally occurring compounds. Antioxidants are generally defined as those products which, naturally, prevent or lessen the body's oxidation. Oxidation refers to the addition of oxygen, and consequent lessening of hydrogen, from an element - be it the body or something else. Antioxidants are found in the nutrient antioxidants, vitamins A , C and E , and the minerals copper , zinc and selenium . Other dietary food compounds, such as the phytochemicals in plants and zoochemicals from animal products, are believed to have greater antioxidant effects than either vitamins or minerals.[16] Antioxidants are a diverse group of chemicals that can be naturally found in vegetables, fruits and plants in general. Antioxidants are also synthesized in our body.[17] Antioxidants are widely used as ingredients in dietary supplements used for health purposes. [18] Antioxidants are substances or nutrients in our foods which can prevent or slow the oxidative damage to our body. When our body cells use oxygen, they naturally produce free radicals (by-products) which can cause damage.[19] Antioxidants are molecules that can stop free radicals from reacting with other molecules. This limits the damage they do.[20] Antioxidants are molecules that help prevent cellular damage. Animal studies also have shown that tea may reduce the risk of lung cancer. Antioxidants are responsible for helping our bodies fight off the "Free Radical" damage caused to our bodies cells. The everyday use of antioxidant supplementation and following a healthy diet rich in antioxidant foods will drastically cut down on the breakdown of healthy cells that fall prey to free radicals.[22] Antioxidants are the “heroes” who neutralize the damaging free radicals, and so protect the body against diseases. Antioxidant vitamins are mainly found in fresh fruit and vegetables, and vegetarians and vegans usually eat more fresh fruit and veggies than meat eaters.[23] Antioxidants are called electron donors. They are not only able to give an electron to a free radical and satisfy its balance so it can no longer damage healthy tissue, but it will also give an electron back to a tissue that has been robbed.[24] Antioxidants are the nutritional equivalent of man's best friend - they are loyal protectors and nurturers of our cells, repelling disease, and promoting good health. Antioxidants can come from healthy eating or in the form of supplements, and they include a family of naturally formed components like vitamin A, beta-carotene, lycopene, vitamin E, and more.[25] Antioxidants are substances used by the body to protect itself from damage caused by oxidation. Oxidation is a process that causes damage in our tissues through the work of free radicals.[26] Antioxidants are also widely used as ingredients in the hope of maintaining health and preventing diseases such as cancer and coronary heart disease. [27] Antioxidants are elements in foods such as vitamins, minerals , carotenoids , and polyphenols. These components give foods their distinctive colors-the deep red of tomatoes, the orange of carrots, and the yellow of corn.[28] Antioxidants are used to retard the reaction of organic material with atmospheric oxygen, which can cause degradation. These chemicals are responsible for retarding oxidation during manufacturing, processing, storage, as well as the end product.[29] Antioxidants are the prevention and the cure. This approach applies to general health, not just heart disease.[30] Phytochemicals provide plants with protection from the environmental challenges they face, such as ultraviolet light. When we consume plants rich in phytochemicals, they seem to protect us as well.[31] Phytochemicals and antioxidants are two specific types of nutraceuticals. [32] Dietary antioxidants come to the rescue. These phytonutrients, natural substances found in fruits and vegetables, neutralize free radicals and help prevent cell damage.[34] Dietary antioxidants also exist, such as vitamins C and E, and beta-carotene. Antioxidants can effectively neutralize RNS in the same manner that they neutralize ROS. Dietary antioxidants confer significant protection to gut epithelial cells from pro-apoptotic oxidant stress. The phytochemical mixtures found in the teas, cat's claw and green tea, appear to be more effective than vitamin C in some cell lines and at concentrations that suggest that they may be acting at levels distinct from the mere scavenging of the oxidant signal.[36] Electron-give-away is what antioxidants do. [37] Electrons are involved in chemical reactions and are the substance that bonds atoms together to form molecules. Electrons surround, or "orbit" an atom in one or more shells.[38] Free radicals have at least one unpaired electron, causing the chemical particle to be unstable. To become stabilized the particle must obtain an electron from some another chemical. Free radicals damage lipids, proteins, and DNA (DNA is present in the nucleus of almost every cell, stores all genetic information, and dictates cellular functions). This damage is the root cause of aging.[40] Free radicals can also damage the molecules responsible for moving cholesterol through the bloodstream, resulting in a build-up of plaque in arteries. Researchers believe that lycopene, found in tomatoes, help reduce free radicals. Free radicals are unstable molecules that, at the cellular level, have the potential to damage DNA and pose a threat to cellular health. In varying degrees, antioxidants are produced by the body naturally.[42] Free radicals are molecules with have one electron too much or to less in order to be stable. Free radicals try to steal or give electrons to other molecules, thereby changing their chemical structure.[43] Free radicals are molecules which lack an electron, and are produced naturally by the body as it burns oxygen. Cigarette smoke, UV radiation, air pollution, stress, certain medications, and poor diet also produce free radicals.[44] Free radicals are destructive and unstable oxygen molecules believed to cause aging, cancer, and even cardiovascular disease. The skin expresses free radical damage as unsightly wrinkles, uneven pigmentation and loss of tone and moisture.[45] Free radicals are compounds with unpaired electrons that stabilise themselves by oxidising other molecules - including proteins, carbohydrates, lipids and DNA. In the process they often create more free radicals, sparking off a chain of destruction.[46] Free radicals are unavoidable and are created naturally as your body performs its everyday functions. In fact, they are even necessary for some processes.[47] Free fatty acid (FFA) content in oil is dependent on the quality of oil. They are formed due to breakdown of oil molecules, triglycerides into its components (fatty acids and glycerol).[48] Free radicals alter cholesterol in a process known as oxidation, which is thought to speed up the hardening of the arteries that leads to heart disease. In addition, pomegranates have beneficial effects on hemorrhoids, fertility and blood pressure. Free radicals make the membrane more permeable, allowing the cells to dehydrate (lose water). The membrane of the cell is what is called a lipid bilayer: two layers of fat end-on-end.[50] Free radicals oxidize (damage) cells — leading to aging and cancer. A good way to think of free radicals is to think of them as bullets being fired at our cells.[51] Free radical damage may lead to cancer. Examples of antioxidants include beta-carotene, lycopene, vitamins C, E, and A, and bioflavonoids such as quercetin, catechin, epicatechin, and anthocyanidin. Free radicals may cause damage to cells, possibly resulting in cancer. Formed from normal body functioning, their production is increased by smoking, air pollution, infection, and excessive sunlight.[53] Free oxygen radicals are extremely reactive and can cause damage to body proteins and fats, and also to the hereditary material of cells, known as DNA. The oxygen free radical (super oxide radical) can be converted to even more damaging radicals by a chain reaction.[54] Free radicals are unstable electrons formed during the process of oxidation (a natural process associated with aging and metabolizing foods), as well as from drinking alcohol, exposure to pollution and radiation, smoking, iron overload and extreme exercise. During oxidation, a free radical takes an electron from another source in order to become stable. Radical species may combine to form other more damaging or toxic species such as peroxynitrite (O=NOO¯), a product of superoxide and nitric oxide radical reaction. [56] Radicals can damage cells by reacting with cellular components; this type of damage is called oxidation and can result in serious injury to cells. Given that radicals are produced during normal metabolism, it is not surprising that cells contain antioxidants (molecules that eliminate radicals) to reduce the risk of radical-mediated injury.[57] Studies in people with high blood pressure indicate that consuming dark chocolate may lower blood pressure, while a placebo has no effect. So, while more research, including longer term studies, will be needed, the preliminary evidence about the flavanols in chocolate is promising.[58] Studies have suggested that the antioxidants that occur naturally in fresh fruits and vegetables have a protective effect. For example, vitamin E and beta-carotene appear to protect cell membranes; vitamin C removes free radicals from inside the cell.[59] Studies from international universities and research institutions show that carotenoids have antioxidant effect and protect healthy cells from free radical damage and are thus believed to prevent a range of degenerative diseases. One example is age-related macular degeneration and cataract. Studies have shown antioxidants that neutralize this activity and that occur naturally in fruits, vegetables, green tea, garlic and onions can be effective at preventing DNA damage. [61] Studies have shown that the skin is the last organ of the body to receive antioxidants from the food and supplements that we eat. This has prompted many skin care companies to develop products with antioxidant ingredients that can be applied directly to the skin.[62] Supplement manufacturers are not tightly regulated the FDA. Thus, these companies get away with making unsupported claims simply to make money.[63] Supplements that increase glutathione must provide cysteine. Glutathione levels cannot be increased by ingesting oral cysteine because oral cysteine is potentially toxic and very quickly destroyed in the gastrointestinal tract. Supplementing your diet with well balanced antioxidant vitamins can go a long way in combating toxins and free radical oxidants and in maintaining healthy body cells. [65] Damage by free radicals is one factor thought to contribute to the development of many chronic diseases (22, 23). Damage at the cellular level is never a good thing. Vitamin C is important to the body's biosynthesis of collagen, catecholamine and carnitine and is integral to proper formation of proteins, neurotransmitters, hormones, DNA and RNA in the body. It also functions to help activate vitamin E.[68] Vitamin E, also a powerful antioxidant, is found in almonds, in many oils including wheat germ, corn and soybean oils, and safflower. Vitamin E is also found in nuts, mangos, broccoli and other foods.[69] Vitamin C, vitamin E and carotenoids may help protect against the oxidation of LDL cholesterol by neutralizing free radicals. Scientists suspect that cataracts develop partly as a result of oxidation of proteins in the lens of the eye, and some studies have shown that antioxidants might be effective in reducing age-related macular degeneration and the resulting vision loss.[70] Vitamin A can be toxic in high amounts. Intravenous injections of the antioxidant, glutathione, may protect the bladder from damage caused by cyclophosphamide.[71] Research now shows that, in addition to preventing oxidation, antioxidants perform many other important roles in our bodies, such as reducing inflammation, keeping arteries flexible, and preserving the genetic material in our cells. [72] Research clearly shows that this is the best preventative measure against cancer so far. Research has shown that 60-80 percent of all cancers are a direct result of chemicals in our air, water and food. [74] Flavonoids are responsible for the blues, purples, and greens in foods, and for the yellows, oranges and reds that are not carotenoids. Generally, the darker the color, the more flavonoids are present in foods, but are also present in onions, nuts, and some other light-colored foods.[81] Flavonoids are polyphenolic compounds that are ubiquitous in nature and are categorized, according to chemical structure, into flavonols, flavones, flavanones, isoflavones, catechins, anthocyanidins and chalcones. Over 4,000 flavonoids have been identified, many of which occur in fruits, vegetables and beverages (tea, coffee, beer, wine and fruit drinks).[82] Flavonoids (polyphenols) provide this pungent taste. The more chocolate is processed (such as fermentation, alkalizing, roasting), the more flavonoids are lost. Flavonoids are not only found in the cocoa bean but in many other fruits, vegetables, wines, teas, nuts, roots and seeds as well. Actually, in most of the roots, nuts etc used for medical purposes there is a clear relation between their medical actions and their flavonoid content. Oxygen, an essential element for life, can create damaging by-products during normal cellular metabolism. Antioxidants counteract these cellular by-products, called free radicals, and bind with them before they can cause damage.[85] Oxygen free radicals are normal by-products of cell metabolism. However, at high levels they can cause damage to cells.[86] Oxygen is a life-giving and life-sustaining property allowing for the proliferation of existence on this planet. Yet, oxygen also has an oxidative (rusting) effect on our bodies, and it is this rusting that results from unstable molecules that is at the heart of premature aging.[87] Oxidation makes that apple turn brown and most people don’t find that appetizing. There are ways to stop an apple from turning brown. Oxidation reactions can produce free radicals, which start chain reactions that damage cells. Antioxidants terminate these chain reactions by removing free radical intermediates, and inhibit other oxidation reactions by being oxidized themselves. Harmful pollutants are waging an all-out assault on the human body. From man-made toxicants, such as industrial waste and automobile exhaust, to naturally occurring invaders, such as bacterial toxins in the water supply, toxicants are formidable foes.[101] Harman and all his contemporaries contended that damage was only done to the cell interior. [102] OPC Antioxidants are considered the best antioxidants available to humans. Derived from grape seed extract, pine tree bark and other sources, OPC Antioxidants are a powerful mixture of all natural, free radical neutralizers that provide a plethora of health benefits including increased circulation and blood flow, improved cardiovascular health and improved brain function. OPCs, OligoProanthoCyanidins, are polymers (or chains) of flavans. Catechins are generally more bioavailable and more potent antioxidants than proanthocyanidins.[105]
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