Antioxidant is a molecule that slows or prevents the process of oxidation in other molecules. Oxidation is a chemical reaction that creates free radicals which in turn damage and destroy cells.
Antioxidants fight against these free radicals by destroying them and prevent other oxidation reactions. These antioxidants are therefore often reducing agents like polyphenols and thiols. Though oxidation is necessary for life, they can also prove to be damaging as well. Therefore animals and plants have several types of
antioxidants like vitamin C, glutathione, vitamin E and enzymes like superoxide dismutase, peroxidases and catalase. Oxidative stress is caused due to low antioxidant levels.
Antioxidants can be found in foods in the form of vitamins, caretinoids, polyphenols and vitamins. Many
antioxidants are identified with their distinctive colours. Foods which are orange in color are rich in betacarotene. Other foods in this category include apricots, pumpkins and carrots. Green vegetables are important for healthy eyes and are known for lutein. Foods like spinach and kale contain lutein. Tomatoes are deep red in colour and are rich in lycopene. Foods containing
vitamins A, C and E are rich in antioxidants.
Antioxidants are thought to be safeguards against oxidative damage and help in maintaining good health. Though research is still underway on to find how effective these antioxidants are, evidence suggests that individuals have benefited from the
antioxidants present in blueberries, grapes, cocoa, and teas in preventing Alzheimer’s disease, cardiovascular health and even in cancer in some cases.
Antioxidants are broadly classified in two divisions depending upon the solubility factor. Antioxidants are either soluble in water known as hydrophilic or in lipids known as hydrophobic.
Water-soluble antioxidants respond with oxidants in the cytoplasm of the cell and the blood plasma while lipid-soluble
antioxidants help in protecting cell membranes from lipid peroxidation.These compounds may be manufactured in the body or taken from the diet.The various antioxidants are available at a wide range of concentrations in body fluids and tissues. Antioxidants like glutathione or ubiquinone re present mostly within cells, while others like uric acid are more or less evenly distributed.
The efficiency of one antioxidant may depend upon the function of other units of the antioxidant system.
Foods which are rich in antioxidants are those hich conatin Vitamin C, Vitamin E, polyphenolic
antioxidants and carotenoids. Some antioxidants are manufactured in the body and are not absorbed in the intestine, for example glutathione which is produced from minno acids. Vitamin C or ascorbic acid is a monosaccharide
antioxidant which is available in both animals and plants. It is reducing agent capable of neutralizing reactive oxygen species like hydrogen peroxide. Since humans cannot synthesize vitamin C, it must be taken from the diet. Most of the other animals are capable of producing vitamin C in their bodies and are not necessary in their diet.
Antioxidants play an important role in treating various diseases. The brain is suseptible to oxidative injury and therefore atioxidants are frequently used for treating various types of brian inury. Amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease are treated with antioxidants.
