Saw this interesting (if a few years old) article at the New Yorker online site: The Height Gap -- Why Europeans are Getting Taller and Americans Aren't by Burkhard Bilger.
Bilger interviewed an economic and anthropometric historian named John Komlos, who's devoted much of the past thirty years to studying people's heights.
For obvious reasons (being 4' 11.5") I was interested. Yes, that 0.5" is of crucial importance. It means I'm taller than my mom.
One might assume that the European eugenicists are alive and well, but I'm not so sure. I think it's just a really cool thing to study. It certainly measures broadly and isn't to be interpreted on an individual basis. I think I can probably attribute my paucity of altitude to sheer genetics. I came from really short stock. Not only that, I'm taller than the generations of women who came before me... but not taller in comparison to my peers, necessarily. I hope that my biological son will achieve at least his dad's height (5'8"), which seems pretty likely because my own dad is also somewhere in that neighborhood as well.
My mom's parents had four children. Of the three girls, the eldest is about 4'10"; each successive girl was taller. In my own family, my mom is 4'11". At my peak I'm pretty sure I hit 5'0" on the nail for several years. My younger sister, born when my parents were 15 years more mature and living a much more prosperous life in general, is comfortably past the five-foot mark.
According to the article, however, the national average for height (even normed for race variations) is just not increasing the way one would assume a prosperous society to. Northern Europeans such as the Dutch, the Danes and the Swedes ARE still getting taller. The article suggests that it's the more readily available and free prenatal and infant health care, among other things. I personally think they're going to start downtrending soon, like us, because of the influx of new diseases and economic issues they're importing in. But I'm not an expert, so I dunno.
[shrug] I'm not one bit interested in the whole "master race" crap... but I do think that population-wide studies are interesting and beneficial simply for the sake of understanding big-picture trends and the effects of stress or ease on a people at large.