Fascinating:

While about 80 percent of height is determined by genes, auxologists (those are height scientists) now believe that nutrition and sanitation determine much of the rest. As the New Yorker’s Burkhard Bilger  put it in 2004:

“Height variations within a population are largely genetic, but height variations between populations are mostly environmental, anthropometric history suggests. If Joe is taller than Jack, it’s probably because his parents are taller. But if the average Norwegian is taller than the average Nigerian it’s because Norwegians live healthier lives.”

Your childhood environment can give you (or take away) three or four inches. A lack of nutrient-rich food and clean water explains why stunting is prevalent among children in developing countries. Studies of North Koreans found that those born after the country was divided in two were about two inches shorter than their counterparts in the South.

When Barry Bogin, an anthropologist at Temple University, measured the heights of children from the Maya ethnic group, he found that Maya refugee children growing up in the United States were about four inches taller than Maya children who were still living in their native Guatemala. He chalked up the difference to America’s superior nutrition and healthcare.

The rest of the article dives into other factors that contribute to height.