The introduction of cultivated cereals and vegetables, along with dairy produce, resulted in a poorer diet and a consequent decline in human stature, only reversed (at least in developed countries) in the last century.

ECONOMIST: Food in history

In most parts of the world Coke's sales are driven by the famous fizz, with richer countries, where calories are all too abundant, leaning increasingly towards Diet Coke, developed in 1982, and poorer countries leaning towards the original sugary stuff dating back to the 19th century.

ECONOMIST: Coca-Cola strikes it rich in Asia with a new drink

To the untrained eye like my own, Dean's cattle look in rude health but he shakes his head and explains, with their restrictive diet, his dairy herd is producing less and poorer quality milk.

BBC: British farmers 'hanging on by their fingertips'