Why do people grow 10 centimeters every 100 years?

Recent studies in England have shown that the height of a 20-year-old soldier during the First World War averaged 168 cm, which is 10 cm less than a modern British soldier. This dynamic is typical not only for Albion, but also for the French, Italians and Swedes, and the Danes and Spaniards grew by 12.5 cm during this time.
One of the most important factors affecting growth is the biological standard of living. During the period of capitalism, average growth declined. But in the 20th century, in developed European countries and the United States, with rising incomes, nutrition significantly improved, which did not slow to affect the increase in average growth.

Respiratory and gastrointestinal infections among children, especially pneumonia, bronchitis, diarrhea and dysentery, have had negative effects on human growth in the past. Equally important was the reduction of prison overcrowding.

According to the results of the military census in 1901, it was found that young men from middle-class families were higher than their peers from large families. Today, other factors, such as advances in medicine and education, contribute to the increase in average growth. It turned out that educated parents had higher military personnel.

Source: techcult.ru