Genetics determine your potential. Nutrition and health allow you to reach your potential. Differences between developed countries mostly come down to genes. Japanese people aren't short because of malnutrition.
Of course, genetics also play a role, and long lasting practices with it. Anthropologists believe early indo-europeans developed a tolerance for lactose that other peoples didn't have, which gave them a plentiful source for calcium in cows milk. From this they got a foot's height advantage over the corded wear people living in Europe at the time - the current Europeans are descendents of these tall milk drinkers.
We also see this in Japan and South Korea - prosperous, developed nations, with excellent benefit systems, but they're very short on average.
Therefore, its a mix of both nourishment and genetics.
Note: You can also try the state version here.
With the Dutch average for women, i can't help remembering that some people doubted if my mother was really my mother, because she is quite small (like 1 meter 56). Quite funny when people actually openly doubt that. :P
When I compare my own country to for example Poland, Lithuania, Hungary, Serbia, Norway, Denmark or Austria, I really don't think we're (Dutch) taller on average. In fact I have the impression we're even shorter. But differences are very small between basically every european country, so it's hard to tell.
Taking a look at wikipedia, the fact we often turn out to be the tallest could be because the Netherlands relies on self-reported data, while in many other countries they measured some sample group
I am 175cm and considered small here in the Netherlands. When I lived in Northern Ireland I felt relatively tall, which was nice for a change!