In the present society in India the average longevity (life span) is around 66 years for men. The life span was 61 yrs a decade ago. In most of the countries in Europe the life expectancy is around 80 years. This tells a lot of things.
Longevity is affected by genetics (genes) of the individuals to some extent.
Longevity is affected to a large extent by the food habits, the living environment, water quality, air pollution, working environment, body fitness, tensions and stresses faced, habits like liquor, smoking, malnutrition, and accidents. Long ago availability of health services to all people, especially in rural areas, were not available easily.
In the last decade the living conditions, life styles of the people and the health services have improved. People are more educated about health and hygiene.