Better quality of nutrition - more protein and vegetables. Much more vegetables. An absurd amount more vegetables.

They also fixed their zinc deficiency, which has long been known to affect height.

But seriously, the vegetables.

Graphs pictured:

• Daily supply of calories that are available for consumption, Measured in kilocalories per person per day. 1985 to 2023
• Estimated share of the total population in each country with zinc intakes below physiological requirements, 1990–2005
• Average daily per capita protein supply, measured in grams of total protein per day, 1985 to 2023
• Average per capita vegetable consumption, measured in kilograms per person per year, 1985 to 2023