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PolyphenolsÂ are a smaller class of antioxidants, which scientists often refer to as "phenols." (Terms like phytonutrient and phytochemical are more generic terms that researchers sometimes use to describe nutrients and chemicals in plants.)
We have clear science about antioxidants, that our bodies need a Natural Antioxidant Defense Network, for lack of a better term the human body needs defense workers at all levels in the form of antioxidants.
How Antioxidants Help Prevent Oxidation
As oxygen interacts with cells of any type, in your body, the cells lining your lungs or in a cut on your skin -- oxidation occurs. This produces some type of change in those cells. They may die, such as with rotting fruit. In the case of cut skin, dead cells are replaced in time by fresh, new cells, resulting in a healed cut.
This birth and death of cells in the body goes on continuously, 24 hours a day. It is a process that is necessary to keep the body healthy. Oxidation is a very natural process that happens during normal cellular functions,
Yet there is a downside. While the body metabolizes oxygen very efficiently, 1% or 2% of cells will get damaged in the process and turn into free radicals,
"Free radicals" is a term often used to describe damaged cells that can be problematic. They are "free" because they are missing a critical molecule, which sends them on a rampage to pair with another molecule. "These molecules will rob any molecule to quench that need,
THE DANGER OF FREE RADICALS
When free radicals are on the attack, they don't just kill cells to acquire their missing molecule. If free radicals simply killed a cell, it wouldn't be so badâ€¦ the body could just regenerate another one. The problem is free radicals often injure the cell, damaging the DNA, which creates the seed for disease.
When a cell's DNA changes, the cell becomes mutated. It grows abnormally and reproduces abnormally -- and quickly.
Normal cell functions produce a small percentage of free radicals, much like a car engine that emits fumes. But those free radicals are generally not a big problem. They are kept under control by antioxidants that the body produces naturally
External toxins, especially cigarette smoke and air pollution, are free radical generators, Cigarette smoke is a huge source of free radicals. In fact, our food and water also harbor free radicals in the form of pesticides and other toxins. Drinking excessive amounts of alcohol also triggers substantial free radical production. Free radicals trigger a damaging chain reaction, and that's the crux of the problem. Free radicals are dangerous because they don't just damage one molecule, One free radical can set off a whole chain reaction. When a free radical oxidizes a fatty acid, it changes that fatty acid into a free radical, which then damages another fatty acid. It's a very rapid chain reaction.These external attacks can overwhelm the body's natural free-radical defense system. In time, and with repeated free radical attacks that the body cannot stop, that damage can lead to a host of chronic diseases, including cancer, heart disease, Alzheimer's disease, and Parkinson's disease.
Oxidative damage in skin cells is caused by cumulative sunlight. But if free radicals are in an internal organ - for example, if asbestos is in your lungs -- it stimulates free radical reactions in lung tissue. "Cigarette smoke has active free radical generators," says Blumberg. That's why stopping smoking is the biggest step anyone can take to preserving their health.
ADVANTAGES OF ANTIOXIDANTS TO HUMAN PHYSIOLOGY.
It has been stated that we need antioxidants for our physical well being, Free radicals causeÂ cancer cells to grow. Antioxidants can neutralize cancer cells before they develop into a mass.
Antioxidants slow the effects ofÂ aging Free radicals damage the cells within our body that are vital to a youthful appearance and goodÂ health Antioxidants can slow down the loss of muscle elasticity that leads to wrinkles, boost your immunity making you less susceptible to illness, and put the brakes on memory failure, as free radicals injure the brain cells necessary for retaining information. Antioxidants are available in supplement form but are the most powerful when found in whole foods. The cholesterol in our bodies is not necessarily harmful until it becomes oxidized, which then causes it to start clinging to our blood vessels which as you know can then lead to some serious health related heart problems. Antioxidants can help to prevent this and thus make a very positive contribution to your overall general state of health and physical well being. They can also provide other benefits to your skin and hair
DISADVANTAGES OF ANTIOXIDANTS TO HUMAN PHYSIOLOGY
Antioxidants is of great benefit to our human well being but could subsequently be dangerous stress, aging, and environmental sources such as polluted air and cigarette smoke can add to the number of free radicals in the body, creating an imbalance of the free radicals in our body The highly reactive free radicals can damage healthy DNA and have been linked to changes that accompany aging (such as age-related macular degeneration, a leading cause of blindness in older people) and with disease processes that lead to cancer, heart disease, and stroke Researchers in K-State's Cardio respiratory Exercise Laboratory have been studying how to improve oxygen delivery to the skeletal muscle during physical activity by using antioxidants, which are nutrients in foods that can prevent or slow the oxidative damage to the body. Their findings show that sometimes antioxidants can impair muscle function. Poole said antioxidants are largely thought to produce better health, but their studies have shown that antioxidants can actually suppress key signaling mechanisms that are necessary for muscle to function effectively. It has been observed that there is a potential for antioxidants to reverse or partially reverse some of those changes that result from hydrogen peroxide, and are helpful to increase blood flow. We're now learning that if antioxidant therapy takes away hydrogen peroxide - or other naturally occurring vasodilators, which are compounds that help aging or disease. However, K-State's studies have shown that some of the oxidants in our body, such as open blood vessels - you impair the body's ability to deliver oxygen to the muscle so that it doesn't work properly.
MEASUREMENT LEVEL IN FOOD
Measurement of antioxidants is not a straightforward process, as this is a diverse group of compounds with different reactivities to different reactive oxygen species. In food science, the oxygen radical absorbance capacity (ORAC) has become the current industry standard for assessing antioxidant strength of whole foods, juices and food additives Other measurement tests include the Folin-Ciocalteu reagent, and the trolox equivalent antioxidant capacity assay. In medicine, a range of different assays are used to assess the antioxidant capability of blood plasma and of these, the ORAC assay may be the most reliable. Antioxidants are found in varying amounts in foods such as vegetables, fruits, grain cereals, legumes and nuts. Some antioxidants such as lycopene and ascorbic acid can be destroyed by long-term storage or prolonged cooking. Other antioxidant compounds are more stable, such as the polyphenolic antioxidants in foods such as whole-wheat cereals and tea. In general, processed foods contain less antioxidants than fresh and uncooked foods, since the preparation processes may expose the food to oxygen.
Foods containing high levels of these antioxidants
Vitamin C (ascorbic acid)
Fruits and vegetables
Vitamin E (tocopherols, tocotrienols)
Polyphenolic antioxidants (resveratrol, flavonoids)
Tea, coffee, soy, fruit, olive oil, chocolate, oregano and red wine.
Carotenoids (lycopene, carotenes)
Fruit and vegetables
Some antioxidants are made in the body and are not absorbed from the intestine. One example is glutathione, which is made from amino acids. As any glutathione in the gut is broken down to free cysteine, glycine and glutamic acid before being absorbed, even large oral doses have little effect on the concentration of glutathione in the body. Ubiquinol (coenzyme Q) is also poorly absorbed from the gut and is made in humans through the mevalonate pathway.
In conclusion, it has been seen that antioxidants are effective in disease treatment and prevention. Also antioxidant supplements may also prevent any of the health gains that normally come from exercise, such as increased insulin sensitivity but as much as antioxidants are important, too much of them can also be dangerous to the health.