Turbulence Risk versus a/c weight

[fireflybob]

I was under the impression that although turbulence feels worse at light weights it was potentially less damaging to the airframe and vice versa.

Is this true and can anyone supply the aerodynamical/physics reason(s) why turbulence is more hazardous at higher weights?

Note:- Am not referring to buffet boundaries with respect to weight versus altitude.

Thanks for any help