Tofu

Plain tofu is a non-event toxicologically. It is coagulated soy protein and water, it digests reasonably well, and a small cube of unseasoned firm or silken tofu is not going to poison a dog. Where owners get into trouble is treating it as a protein source rather than a treat. A bowl of tofu is not an AAFCO complete-and-balanced diet: it does not carry the amino acid profile, calcium-to-phosphorus ratio, or micronutrients a dog needs, so substituting it for food creates a nutritional deficit rather than a health upgrade. Keep treats, tofu included, inside the usual 10 percent of daily calories. Two real caveats. Soy is one of the more commonly reported dietary allergens in dogs, which is exactly why so many US limited-ingredient and novel-protein diets are marketed as soy-free. If your dog scratches, licks paws, develops red itchy ears, or has loose stool after soy, talk to your veterinarian about a proper elimination diet rather than guessing. Second, soy ferments in the colon, so a generous serving produces gas, bloating, and soft stool. You may still see older articles claiming soy causes gastric dilatation-volvulus; later research has challenged that link, so it should not be repeated as established fact. It is still not a reason to feed a large portion at once. The seasoning is what actually hurts dogs. Teriyaki-glazed, garlic-marinated, soy-sauce-braised, or chili-oil tofu brings sodium and alliums to the bowl, and garlic damages canine red blood cells. If you share tofu, share it plain, unsalted, cut small, and rarely.