Originally Posted by SeanGAR

I'm glad you asked that question.

Being hydrophilic, goodness is typically attached to the cellulose molecules in the tobacco leaves by hydrogen bonding. The early hypothesis suggested in the 1950s that goodness is attached to the lignins in the tobacco has been shown to be false.

However, as water molecules are present in the environment (70% humidity is RELATIVE humidity of course, and that is relative to pure water at that same temperature and pressure), they compete for the goodness binding sites on the cellulose.

It comes as no surprise, thus, that storage at very high humidity causes problems. For one, goodness molecules are freed up and molds are able to feast on them. For another, long term storage at high humidity results in a LGC ... that would be Low Goodness Cigar, for the noobs.

So not only should cigars be stored foot up, but at humidity where the goodnes is not out-competed by water molecules. That has been shown to be around 60-70% RELATIVE humidity.

Storage at too low humidity results in activation of GD enzymes. That would be Goodness Destroying enzymes, for the noobs. That is why you can't store cigars at too low or too high humidities. It all relates to dG/dt .. or the rate of goodness change with time.