For millennia, people have altered food to please their palates. More than 3000 years ago, Mesoamericans, living in what is Mexico and Central America today, cooked corn kernels in a solution of wood ash or limestone. The process, known as nixtamalisation, unlocked nutrients and softened the tough outer shells of the corn, making them easier to grind.

With the invention of canned goods and pasteurisation in the 19th century, food alchemy became possible on an industrial scale. Processing innovations made food cheaper, more convenient and plentiful. According to the UN, the average daily food supply available for a person in the rich world increased by over 20 per cent between 1961 and 2021, to 14,644 kilojoules. In that time, obesity rates have more than tripled – today, nearly one in three people globally are obese or overweight.

The Economist