I was looking for suggestions on what kind of wood would make a light weight kitchen table. It has to be strong enough to hold up as a bed also. The first one I made is way to heavy to keep. Thanks
+1 on the torsion box. But realize a thin skin might be punctured (think hollow core door). You'll need to reinforce the area(s) where the leg(s) attach.
Cypress has one of the best strength-weight ratios,I'm told. It too, though is soft and vulnerable to dings and dents.
A 49" x 97" sheet of 3/4" MDF weighs about 96 lbs. So, yea, it's not light, though there a "lightweight" version.