Half a century ago, most people died before the age of 50. Now, the great majority live well beyond that age. Global average life expectancy at birth reached 65 years in 1996.

Health expectancy can be defined as life expectancy in good health, and amounts to the average number of years an individual can expect to live in a favorable state.

It is vital to realize that increased longevity does not come free.

Every year many millions die prematurely or are disabled by diseases and conditions that are to a large extent preventable.

Longer life can be a penalty as well as a prize.