What theory suggests that population growth will outstrip food supply?

Malthusianism suggests that population growth can outstrip food supply, causing scarcity and crisis.

The idea comes from English cleric and economist Thomas Robert Malthus, who presented it in An Essay on the Principle of Population in 1798. Malthus argued that population tends to grow exponentially when unchecked, whereas food production increases more slowly, often described as arithmetic growth. The resulting pressure could reduce living standards and produce famine, disease, or conflict.

In Malthus’s model, preventive checks such as delayed marriage or lower birth rates could restrain population growth. Positive checks, including famine and disease, could raise mortality when population exceeded available resources. Later writers used the term Malthusian catastrophe or Malthusian trap for this predicted crisis.

The theory has been influential but contested. Agricultural improvements, industrialization, contraception, and demographic transition allowed food production and living standards to rise far beyond Malthus’s expectations in many regions. Malthusianism is therefore best understood as a theory about population-resource pressure, not a guarantee that catastrophe must occur.