Human Carrying Capacity and Human Health. December 28, 2004 PLOS Medicine
The silence around overpopulation prevents the global health community from making the necessary link between the planet's limited ability to support its people and health and development crises. The question has been controversial for over two centuries. In 1798 the Reverend Thomas Malthus put forward the hypothesis that population growth would exceed the growth of resources.
Soon after 1934, the global population began to rise steeply as antibiotics, vaccines, and technology increased life expectancy. By the 1960s, concerns of a mismatch between global population and global food supply peaked.
In 1966, United States President Lyndon Johnson shipped wheat to India to avert a famine on the condition that the country accelerate its already vigorous family planning campaign. But the 1970s surprised population watchers. Instead of being a period shadowed by calamitous famine, the new crop strains introduced by the "Green Revolution" (especially grains such as rice,
wheat, and maize) caused a dramatic increase in the global production of cereals, the main source of energy in the global diet. By the end of the decade, the public health community felt sufficiently empowered to proclaim "Health for All by the Year 2000". Average life expectancy continued to zoom upwards almost everywhere — even in sub-Saharan Africa.
The introduction of safe contraception contributed to a rapid fertility decline in many countries. But while the rate of global population growth declined from its peak in the late 1960s, the absolute increment of increase in annual global population continued to grow.
The 1970s can be seen as the decade when concern about overpopulation started to fade. The social and economic milieu, especially in the US, started to change. US foreign aid declined from the late 1960s.
The world oil shock in 1973 contributed to a combination of rising unemployment with higher prices — and to increased economic power for the oil-producing countries of the Third World.
Reagan's policies were to cement a new orthodoxy about global overpopulation and development strategies. In the same year, the US surprised the family planning world by abdicating its leadership in the effort to promote global family planning. The US took this position against the opposition of the Population Association of America, which represented many US demographers.
As foreign aid budgets fell, the "Health for All" targets began to slip from reach. The increased domestic inequality of recent decades in developed countries probably also contributed to a reduction in concern for the Third World. It is clear that market deregulation and high birth rates have proven disastrous in many Third World countries.
Overpopulation is hardly considered, except by dissident public health workers, the discipline that would appear to be the most likely holder of the Malthusian baton, is now almost entirely silent about overpopulation in developing countries. On the other hand, the role of the transition in China from large to small families, with an average of two or fewer children is rarely credited as central to the Chinese economic miracle.
The silence on overpopulation is the "Hardinian Taboo", named after the American ecologist Garett Hardin, who described the taboos that humans use to avoid confronting the need for population control. Social norms inhibit debate about overpopulation in one of the world's most intractable trouble spots, Israel and Palestine.
Human carrying capacity is the maximum population that can be supported at a given living standard. This apparently simple concept has many nuances and is rarely used by population scientists. It is irrefutable that human ingenuity and cooperation can increase human carrying capacity . But even so, human welfare will continue to depend on the external world, including for resources such as food and water. rw Karen Gaia says: Again, the term 'population control', which implies the author thinks that some kind of control is necessary. What really works, and has been proven, is enabling people to choose their own family size - strictly voluntary, without pressure. 
