This study asked whether a novel saliva-based diagnostic test could predict food sensitivities and intolerances in cats. Clinical samples were obtained from 1000 cats proven or suspected to have adverse food reactions (AFR). Most were domestic shorthairs over 10 years old and weighed around 5 kg; they were equally distributed between spayed females and neutered males. Saliva was collected after at least an 8-h fast with a dental cotton rope, placed in a special saliva collection tube, and sent to the laboratory. Salivary reactions to 24 common foods were measured with immunological reagents. Low reacting foods were lamb, cow milk, pork, turkey, wheat (lowest) and white-colored fish, whereas high reacting foods were millet, white potato, rice (highest) and salmon. Thus, this novel salivary-based food sensitivity and intolerance test, described previously for dogs, also provided a reliable and clinically predictive alternative to other methods of measuring AFR in cats.