Essay example --

Free radicals play an important role in several biological processes such as cell signaling and redox regulation. However, prolonged exposure to free radicals leads to oxidative damage. Subsequently, it has been implicated in the progression of several diseases like cancer, cardiovascular disease, neurological disease, pulmonary disease, rheumatoid arthritis, nephropathy, ocular disease and pre-eclampsia. The antioxidant defense system within the body may confer protection to oxidative damage by scavenging free radicals. Antioxidants also may be obtained from dietary sources/ supplements. The efficacy of antioxidant intake on initiation and progression of chronic diseases will be reviewed. Introduction Oxygen is an element that is crucial for the sustenance of life on earth. It is paradoxical that this indispensable element can cause harmful effects in humans under certain circumstances. Much of the detrimental consequences of oxygen are attributed to its ability to form free radicals (1) . A free radical is a reactive molecule that contains at least one unpaired electron in its outer orbit, and is capable of independent existence (2).Accumulation of these molecules in the body results in oxidative stress, a process by which physiologically important molecules such as carbohydrates, proteins and lipids are damaged (3). However, the body can employ antioxidants to impede the threat of free radical attack (4).Antioxidants are potent scavengers of free radicals (1). They function by donating an electron to a free radical or by eliminating initiators of free radicals (5). Antioxidants may be classified as endogenous or exogenous depending on their mode of acquisition by the body (1). E ndogenous antioxidants are naturally produced by t... ...ment dosage and duration of treatment. Moreover, a host of lifestyle behaviors are responsible for determining the health of individuals. Antioxidant intake in combination with physical activity, and alcohol and tobacco moderation may yield profound benefits in disease management. Thus, multifactorial interventions may serve as alternative strategies in disease management. Finally, investigations on the effects of nutrients in isolation may provide valuable information regarding its mode of action, but do not elucidate the phenomenon of total diet. The intrinsic nature of diet is characterized by several interactions between bioactive dietary components, some of which still remain unexplained. Hence, antioxidant supplements must be prescribed with caution and the use of antioxidant rich foods as disease prevention agents may hold promise in future clinical trials.