imho
if this detail is adressed it should be temporary, not permanent.
Maybe a remark after weightloss but no permanent condition.
Weight, Fitness and the resulting conditions should be very flexible!
Becasue of gameplay, not realism ofc.
You should be able to move back and forth in an endless game.
Ofc some things, like height, base skincolor, eye color and base haircolor should be permanent.
Ps.: I suggested a tanning system (also non permanent ofc.) and the dev was very positive on it.