Put an extra dining hall and food/drink stockpiles near your smelters. Dwarfs take "eat" as a job, either from idling or, if they've been busy smelting, after finishing a workshop job; they'll then first locate a piece of food that's close to them the moment they decide to go eat, and once they've found food, they'll go looking for a chair.
Offering dining accomodations (and if necessary a makeshift crash space) near their workshops cuts down quite a lot on unproductive cross-fortress travel on self-maintenance jobs.
Do you have enough commonly available chairs? "Lack of chairs" usually comes up when there are either too few chairs around (a rare occurrence, one chair-with-table for five dwarfs should be comfortably enough, but more don't hurt) or some dwarfs can't find a legal chair to sit on because all other chairs already belong to somebody, i.e. are assigned to personal dining rooms or offices. This _usually_ doesn't happen by accident, since dwarfs won't claim unassigned dining rooms like they claim unassigned bedrooms.
But if a chair/table is _in_ a room that's an individual dwarf's property, it becomes unavailable to anybody else. If, say, you paint a huge personal bedroom from a stray bed in the middle of the dining hall, the owner of the bed will now be the proud owner of all those chairs and tables and no-one else will dare eat there. At least that's what i remember, haven't fallen in that trap for quite a while now.