Aging researchers currently acknowledge only two life-extending interventions in mammals: calorie restriction and genetic manipulation. The free radical theory of aging put forth by Denham Harmon from the University of Nebraska College of Medicine in 1954. This theory did not have much support from the medical community until the early 19905, when results from studies by scientists began to show that oxidative damage to human cells accumulates with age and is a major contributor to degenerative diseases such as cancer, Alzheimer's disease, cardiovascular disease, and nervous system dysfunction. Free radicals are formed in the body as by-products of cellular metabolism. Chemically a free radical is a molecule highly reactive with at least on unpaired electron. Since reactive or unstable molecules strive to achieve a stable, neutral state, free radicals circulate through the body on a mission to stabilize their electron structure. During this process, they attack the DNA, lipid membranes, and cellular proteins of the body. The number of free radicals in the body is increased by environmental factors such as chemicals, pesticides, cigarette smoke, air pollution, UV exposure (sun light), radiation, stress, age, and fried, processed foods. Some experts estimate that free radical activity is involved in 80 - 9096 of degenerative diseases. Antioxidants are compounds that control the damage caused by free radicals and neutralize free radicals. Our bodies produce antioxidants to neutralize free radicals, but the levels of antioxidants decrease in aging process.
Human quest for youth begins from ancient times and continues from the twentieth century until today. Pre scientific beliefs were governed by animistic forms of thoughts leading to attempts to control aging, disease and death through magic and supernatural agencies. Careful adherence to nutrition, hormonal and cell based therapies, genetic manipulations, other medications and supplements can increase one's chances of living a healthy life. The world Health organization has clearly recognized the utility of Ayurveda system of medicine to fulfill the World wide health need of present scientific era. To study the concept of resistance against disease in terms of immunity and the idea that such resistance can be modified by using several pharmacologic and non pharmacologic approach is of clinical use. In ayurvedic system of medicine several natural medicinal plants have been mentioned which are being used as a potent agent to modify the cell regeneration, cell longetivity with cytokinetic and cytogenetic improvement to retard the ageing.