chapotraphouse

Just to add on to your point, this effect has been shown to be triggered over a relatively short period of time. The Dutch Hunger Winter of 1944-1945 caused by the Nazis blockading urban centers in the Netherlands under their control from the rural food producing areas triggered this epigenetic adaptiation in the children and pregnant mothers (who passed it on to their then unborn children) that were affected. All from a single famine lasting from roughly late September/early October 1944 until early May 1945.