Oxidative stress often occurs as a side effect of normal human functioning. When cells in the human body use oxygen to make energy, they can create reactive molecules known as free radicals. Free radical molecules are unstable because they lack an electron. Inside the body, they can potentially react with almost any other molecule. Oxidative stress is the cell damage associated with the chemical reaction between free radicals and other molecules in the body.
The cell damage caused by oxidative stress is believed to be behind a number of illnesses, such as cancer or autoimmune disease. The body generally uses nutrients known as antioxidants to control cellular stress. Antioxidants are believed to boost immunity, as well as preventing cancer, heart disease, diabetes, and macular degeneration. Antioxidants may even help to slow the signs of aging and progression of Alzheimer's disease.
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Oxidative stress usually occurs when there are more free radicals than antioxidants in the body. When free radical and antioxidant levels are imbalanced, free radicals are left to bond chemically with the cells of the body. Free radicals are so unstable that they can react with almost any other type of molecule. They are believed capable of significant damage to cells and proteins in the body. Free radicals may be responsible for damaging a cell's DNA so that the cell mutates and reproduces out of control, forming a cancer.
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Some amount of oxidative stress is almost always an inevitable result of aging. Other factors that can contribute to oxidative cellular stress include cigarette smoking, pollution, exposure to excess sunlight, and poor nutrition. Doctors believe that cellular stress can be largely controlled by avoiding cigarettes, using UV protection, and eating a diet high in antioxidants.
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Antioxidants are nutrients that generally act to cleanse the body of free radicals by giving up an electron. When a free radical molecule takes an electron from an antioxidant molecule, the free radical stabilizes. Once stabilized, the free radical can no longer cause damage.
Common antioxidants include vitamins A, C, and E. Zinc, selenium and plant polyphenols are well-known antioxidants. Antioxidants are most often found in fruits, vegetables, herbs, and teas. Medical professionals generally agree that eating a diet rich in antioxidants may help slow the normal progress of oxidative stress.