epigenetic ≠ genetic.

also, just because there is epigenetic degradation due to a change in diet, it is not necessarily indicative of a previous vegan diet (correlation is NOT causation), it just means at one time we ate more of these things than we have been recently.

if you have a machine that functions on two forms of fuel, and then only use one, the machine will not function properly, but the solution is not to only use the other fuel.