Yes, Dogs Can Eat Tomatoes in Moderation. If you want to give your dog tomatoes as a treat, go right ahead. Just make sure that they are washed well, or even better, peeled. Tomatoes are even healthier for dogs if you cook them, because they are in lycopene, an anti-oxidant, which is easier to absorb when tomatoes are cooked. Tomato sauce is also healthy for dogs to eat.