FREE RADICAL

noun (Health and Fitness) An atom or group of atoms in which there is one or more unpaired electrons; an unstable element in the human body which, it is thought, can be overproduced as a result of chemical pollution and may then cause cell damage. Etymology: Formed by compounding; free in its chemical sense means 'uncombined' and radical denotes an atom which would normally form part of a compound. History and Usage: As a chemical term, free radical has existed since the beginning of this century. What has brought it into the public eye in the past few years is the interest shown by the alternative health movement and environmentalists in free radicals as the apparent link between pollution and late twentieth-century health problems such as cancer and Alzheimer's disease. Vincent Lord knew that many drugs, when in action in the human body and as part of their metabolism, generated 'free radicals'. Arthur Hailey Strong Medicine (1984), p. 159 Increasingly essential are the anti-oxidants--vitamins A, C, E and the mineral selenium, which bolster the body's natural defence against disruptive free radicals. Generated in the body as a result of radiation, chemical pollutants, medicinal drugs and stress, free radicals can damage cells and tissues bringing about premature ageing. Harpers & Queen Apr. 1990, p. 143