What is meant by ‘old’? Chronological age cannot be used to define physical and mental abilities. The human being is the product of his genetic heritage as well as his past and present environment, including the injuries, infections, stresses, fatigues, nutritional imbalances and emotional trauma associated with them. It therefore stands to reason that the longer a person lives the more complex he becomes and that the physical and physiologic variations found in 70 years old persons, each of whom have been subjected to widely different environments make them a very heterogenous group. Old age should be regarded as a normal inevitable biological phenomenon. Ageing is a universal process.