Two quick slot menus, and +1 for the great radial menu idea. Bound to two different keys.
Option 1
The radial menu could auto populate with what you have on you at the time.
Option 2
The radial menu could be a static menu which highlights and makes selectable only the items you have on you at the time.
Selecting the item (weapon or health - e.g. berries) equips it.
You would then need to chose to consume it as you do currently.