The absolute growth in average height? For sure. But a lot of these changes in lifestyle happened in steplock with other European countries (sweden, norway, germany) so they don't necessarily explain why we had such massive growths relative to other European countries. Epigenetics are interesting, offspring of survivors of the winter of 1944 (what we call "de hongerwinter") had a tendency towards obesity, more so than people who were born slightly before that winter. I'm not aware of any studies on height and epigenetics. Our country has always been prone to flooding, but if anything, such "evolutionary" pressures have gotten less as we developed more technology to deal with flood-prone areas.