Is the rate of cancer actually low or are a lot of cases never formally diagnosed? People in India might not "exercise" much in terms of going to the gym or running but they might still be physically active in other ways.
word of mouth spreads really fast in india. if people are dying horrible deaths of a disease, and cancer sufferers seem to die horribly, it would be known. things like tuberculosis and leprosy became well known. AIDS too. but cancer seems like a disease of the first world.