Stage three: mortality continues to decline but at a slower rate,
fertility begins to fall rapidly, population growth rates slow down
The third stage of the demographic transition sees mortality falling more
slowly. Rising incomes change the pattern of mortality and we see an increase
in ‘diseases of affluence’. In India deaths due to ‘accidents and injuries’
increased from 3.9 per cent of the total in 1966/67 to 9.5 per cent in 1994/95,
which is probably due to greater mechanization of factory production, and
lifestyles and traffic accidents. The share of non-communicable diseases in
rural mortality rose from about 35.9 per cent in 1969–71 to 54.9 per cent in
1994–95, as bronchitis and asthma, heart attack, cancer, and paralysis (includ-
ing strokes) all became more important contributors to mortality. In urban
areas coronary heart disease is closely related to changing lifestyles. The shift
from rural to urban living increases exposure to toxic industrial chemicals, and
various contaminants such as airborne lead from motor vehicles. In Delhi, for
example, the number of cars increased by 12 per cent annually during the
1990s. More sedentary lifestyles, and diets involving a high intake of saturated
fats, meant by the late 1990s an estimated 10 per cent of women in Delhi were
obese and another 25 per cent overweight. The 1998/99 National Family
Health Survey (NFHS) survey found that 28 per cent of males over the age of
15 years chewed tobacco, and 29 per cent smoked. The figures were increasing
among women and had reached 12 and 2.5 per cent respectively (Visaria,
2005). When life expectancy reaches about 65 further reductions in mortality
are much harder, more expensive and slower. They require more expensive
medical treatments for cardiovascular disease and cancers, and lifestyle
changes, such as more exercise, less smoking and a healthier diet. In India life
expectancy has continued to increase, though at a diminishing rate, from (for
males) an average of 36.8 years in the 1950s, to 44.0 in the 1960s, 50.0 in the
1970s,55.5 in the 1980s and 60.8 in the 1990s (Dyson, 2005:21).
88 Sources of Growth in the Modern World Economy since 1950
Box 4.2 Potatoes: The First Wonder FoodAn earlier shift in the relationship between income and mortality resulted from
the introduction of potatoes from the New to the Old World after 1492. Potatoes
were nutritionally superior to previous (before c1700) staple crops. They
provide nearly all the important vitamins and nutrients necessary to life (Nunn
and Qian, 2011:599). Humans can be healthy on a diet of potatoes supplemented
with dairy (providing vitamins A and D, which potatoes lack). An acre of pota-
toes yields approximately three times more energy than an acre of wheat, barley
or oats. Old-World population growth after 1700 was more pronounced in
regions suitable for potato cultivation. Careful statistical analysis shows that
introduction of the potato can explain 26 per cent of the increase in Old World
population and 34 per cent of the increase in Old World urbanization between
1700 and 1900 (Nunn and Qian, 2011).