From ‘a comma in a sentence. Extraordinary change in an ordinary family over six generations’ by R Gopalkrishnan

….Grant happiness study which followed the developments in the lives of 268 men in the Harvard class of 1937. For seventy-three years the study tracked all areas of their life…..

The study identified six variables which contribute to human happiness:

i.                    education

ii.                  stable relationships

iii.                not smoking or alcohol abuse

iv.                warm cohorts: siblings, school friends and others

v.                  exercise and healthy weight

vi.                healthy adaptation