Which alcohol is gluten-free?

Anything not made from wheat, barley or rye: tequila and mezcal from agave, rum from sugarcane, cognac and wine from grapes, potato and corn vodka, mead from honey. Grain spirits like scotch, bourbon and most gin are gluten-free in practice because distillation removes the protein, but US rules bar them from the label. Beer is the genuine exception, because it is not distilled at all.

Yes. Gluten peptides are far too large to carry over in the vapour, which is why the Celiac Disease Foundation and Beyond Celiac both consider distilled spirits safe for coeliacs regardless of the starting grain. The disagreement is about labelling, not chemistry: FDA and TTB rules reserve the "gluten-free" claim for products not made from a gluten grain in the first place.

No, and beer is the one category where the answer is a straightforward no. Beer is brewed from malted barley and never distilled, so the gluten stays in the glass. Dedicated gluten-free beers brewed from sorghum, rice or millet exist and are a separate product from the twelve styles ranked here.

It depends on the base. Corn, potato and grape vodkas are gluten-free outright. Wheat and rye vodkas, which is most of the premium shelf, cannot carry the label even though distillation removes the gluten protein.