Ageing broadly describes the biological changes that occur over the course of adult life. These changes lead to a gradual decline in function and an increasing risk of dying. The loss of function associated with ageing manifests itself as a reduced ability to withstand the challenges we face every day such as infections, accidents and illnesses. Not everybody ages at the same rate, and even within a person organs and tissues might age differently. Ageing is thought to be almost universal, although some organisms (such as the Quahog clam Arctica islandica) are thought to not age at all and this suggests that ageing is something that can be targeted.
Although ageing is not itself a disease, it carries with it with an increased risk of many life-threatening diseases and shares several biological mechanisms that are important in the development of chronic diseases, such as heart disease, diabetes and dementia. Thus, if ageing can be delayed it should also be possible to also delay the development of disease, increasing longevity and minimising poor health in old age.
The video below explains the benefits of research into ageing.