Remember how I hypothesized about vitamin D’s ability to prioritize which organ gets vitamin D when levels are less than 40 ng/ml? Think of a mountain with a lake at the top and many streams coming out of the lake to really important gene pools below, and then streams coming out of those to longer-latency (diseases way in the future) pools down, etc. Think of about thousands of total pools on that mountain, some high up and some low down, for the genes in the 38 tissues vitamin D regulates. The gene pools low down do not get much vitamin D unless the lake and upper pools are full. A recent study linked 3,000, not 2,000, human genes to vitamin D, so we are talking a lot of pools.