How to Prevent Free Radicals From Damaging Your Health with the Help of Antioxidants
You have often heard that fruits and vegetables are good for your health. This article will help explain why.
Free radicals are chemicals that are capable of damaging cells and genetic material. They come from the food you eat, the air you breathe, sunlight’s action on the skin and eyes, and the body when it turns food into energy. Free radicals steal electrons from nearby substances, which can drastically alter those substances’ structure or function. They can change instructions coded in DNA, can make LDL (also called bad cholesterol) more likely to get trapped in the arteries, and can alter cell membranes1. Free radicals are thought to contribute to aging and the development of many degenerative or chronic diseases, such as cancer and atherosclerosis2,3,4. Experimental evidence links free radical production to biological damage5,6,7.
Substances that fight free radicals are often called antioxidants. Antioxidants give electrons to free radicals. The most common antioxidants are vitamin C, vitamin E, beta-carotene, selenium, and manganese. Different antioxidants have different roles. This means a wide variety of antioxidants will be more beneficial than any single antioxidant1.
The body makes its own antioxidants. However, some antioxidants cannot be synthesized in the body and must be obtained from diets, mainly from fruits or vegetables. Studies show consumption of fruits and vegetables can increase the plasma antioxidant capacity in humans8. Researchers found kale, blackberries, strawberries, spinach, blueberries, cranberries, and raspberries had the highest antioxidant capacities among common fruits and vegetables9.
Oxygen Radical Absorbance Capacity (ORAC) measures antioxidant capacities, including the ability to combat the effects of free radicals9. The average antioxidant intake from fruits and vegetables in the United States is 1200-1640 µmol TE/day8. Studies suggest an increase in antioxidant intake from fruits and vegetables of 1000-2000 µmol TE/day may be needed to bring about some of the beneficial effects associated with fruit and vegetable consumption9.
Fruits and vegetables have been shown to have many benefits. Consumption of fruits and vegetables has been associated with fewer incidences and deaths from cancer6,10,11,12,13,14,15,16,17,18,19, cardiovascular diseases, and cerebrovascular diseases20,21,22,23,24. Vegetarians and non-vegetarians with a high intake of fruits and vegetables have reduced blood pressure25,26. Research shows the antioxidants in fruits and vegetables help protect against diseases27,28,29,30,31,32,33,34.
The Harvard School of Public Health says the package of antioxidants, minerals, fiber, and other substances found naturally in fruits, vegetables, and whole grains will do a better job preventing chronic diseases than high doses of antioxidants will1.
References:
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