Often heart disease and cancer are initiated by the damage at the cellular level by harmful molecules. A large number of biochemical reactions (metabolic processes) that are essential to life take place in our body.
During these processes, reactive molecules called free radicals (FR) are formed. These are unavoidable by-products of the normal metabolic process. Most of the free radical generated in our body contain oxygen atoms and are therefore referred to reactive oxygen species (ROS).
As they are very reactive FR and ROS could react with other molecules and damage cells tissues and organs in the body.
Not only is free radical generated in this normal process, but they are also generated by the body when exposed to ultraviolet (UV) light from the sun and other forms of radiation. In addition, humans are exposed to free radicals in cigarette smoke, car exhaust, industrial fumes and other environmental pollutants.
Pathogenic micro-organisms and some environmental pollutants could activate our immune system. An activated immune system also generates a lot of free radicals with the tension of destroying the invading pathogens. Although essential in destroying pathogenic micro-organisms, exposure to an excessive amount of free radicals under these conditions could also damage our body tissues and organs.
Exposure of the body systems to excessive free radicals is called ‘oxidative stress’. Prolonged oxidative stress could damage the cells in human organs and lead to disease conditions like cardiovascular diseases (heart disease), cancer, cataract and rheumatoid arthritis. Free radicals are also involved in the ‘aging process. Anti-oxidants in diets could attenuate the ‘oxidative stress’.