Can dogs eat tomatoes?

CONDITIONAL — Ripe, red tomatoes can be an occasional low‑calorie treat for dogs; green parts and unripe fruit contain solanine/tomatine and can be toxic. Watch sauces for garlic/onion.

Quick Safety Summary

- CONDITIONAL: Ripe, red tomato flesh is generally safe for most dogs as an occasional treat. (Give only plain, ripe tomato in small amounts.)

- AVOID: Green tomatoes, stems and leaves — these contain solanine/tomatine (nightshade alkaloids) that can cause GI and neurological signs.

- AVOID tomato sauces that contain garlic, onion, salt, sugar or high fat — these are commonly toxic or unhealthy.

- If your dog eats a lot of green tomato or plant material, contact your veterinarian or ASPCA Animal Poison Control immediately.

CONDITIONAL — Ripe, red tomatoes (the flesh) are generally safe for dogs in small amounts, but green tomatoes, stems, leaves and tomato plants contain solanine/tomatine and may be toxic. Tomato-based prepared foods (sauces, ketchup, pizza) often contain garlic, onion, salt or fat that make them unsafe.

This article explains the nutrition, toxicology and safe serving guidelines so you can make informed choices for your dog.

How tomatoes affect dogs: the bottom line

• Ripe red tomato flesh: low in calories, contains vitamins and antioxidants (not toxic in small quantities).
• Green/unripe tomatoes, stems, leaves and the plant: contain higher levels of glycoalkaloids (solanine and tomatine) that can cause poisoning.
• Processed tomato products: often contain added ingredients (garlic, onion, salt, fat, sugar) that are unsafe or unhealthy for dogs.

Nutrition snapshot: what a ripe tomato gives a dog

Raw, ripe tomatoes are mostly water and provide small amounts of nutrients that can be beneficial in moderation. Per 100 g (about one small tomato):

• Calories: ~18 kcal
• Protein: ~0.9 g
• Fat: ~0.2 g
• Carbohydrates: ~3.9 g (including ~1.2 g fiber)
• Vitamin C: ~13–15 mg
• Potassium: ~200–250 mg
• Lycopene: an antioxidant linked to health benefits (concentration varies with ripeness)

Toxicology: solanine and tomatine (what to watch for)

Tomato plants and unripe green fruit are members of the nightshade family (Solanaceae). They contain alkaloids called solanine and tomatine. These compounds:

• Are concentrated in green/unripe fruit, stems and leaves.
• Can cause gastrointestinal signs (vomiting, diarrhea), hypersalivation, abdominal pain.
• In larger exposures can produce lethargy, weakness, incoordination, slowed heart rate, tremors or even central nervous system signs.

Symptoms of tomato/solanine poisoning

• Vomiting and diarrhea
• Excessive drooling
• Abdominal pain
• Lethargy or weakness
• Unsteady gait, tremors, or in severe cases collapse
• Heart rate changes (less common)

Prepared tomato products: why most sauces are a no‑go

Tomato sauce, ketchup, pizza and other processed tomato products present multiple hazards:

• Garlic and onion (commonly in sauces and pizza) are directly toxic to dogs and cause oxidative damage to red blood cells (hemolytic anemia).
• High salt, sugar, fats and spices can cause GI upset, pancreatitis (if fatty), or salt toxicity in large amounts.
• Additives such as onion powder are concentrated and can be dangerous even in small servings.

Cherry tomatoes and small dogs: can they choke? Serving form matters

Cherry tomatoes and grape tomatoes are often fed as bite‑sized treats. Consider both toxicity and physical risk:

• General choking hazard: whole cherry tomatoes are about the size of a treat; most adult dogs can swallow them without issue, but small toy breeds and puppies could choke. Cut cherry tomatoes in half or quarters for small dogs or supervise eating.
• Nutrition/toxicity: ripe cherry tomatoes are the same as larger ripe tomatoes — low in calories and safe in moderation. Avoid stems and leaves.

Recommended serving sizes by weight

Treats should be a small fraction of daily calories (<10% of daily caloric intake). The following are conservative, practical guidelines for ripe, plain tomato flesh only (no sauce, spices, stems or leaves):

• Dogs <10 lb (4.5 kg): 1–2 small cherry tomato halves (≈5–15 g; ≈1–3 kcal)
• Dogs 10–25 lb (4.5–11 kg): 2–4 cherry tomato halves or 1–2 tablespoons of diced tomato (≈15–30 g; ≈3–6 kcal)
• Dogs 25–50 lb (11–23 kg): 3–6 cherry tomato halves or 2–3 tablespoons diced (≈30–60 g; ≈6–11 kcal)
• Dogs >50 lb (23 kg+): up to 1/2 small medium tomato (≈50–75 g; ≈9–13 kcal), adjusted to overall diet and activity

What to do if your dog eats green tomatoes, stems or lots of plant material (emergency steps)

If your dog has eaten green tomatoes, tomato plant stems or leaves, take action quickly:

Emphasize: green tomato/plant ingestion can lead to significant signs; prompt veterinary advice is important.

Preventing access in gardens and compost piles

If you grow tomatoes or have them in your yard, take steps to prevent canine access:

• Remove lower leaves and prune plants to reduce low‑hanging foliage that dogs can chew.
• Use fencing or plant cages that keep dogs out of beds.
• Use raised beds or containers out of reach of pets.
• Secure compost bins: decomposing tomato plants can still contain alkaloids.
• Train dogs with positive reinforcement to stay out of garden areas; use deterrents (safe bitter sprays) only as manufacturer instructs and check they are pet‑safe.
• Supervise dogs in the garden, especially puppies and curious dogs.

When to skip tomatoes entirely

Avoid giving any tomato products if your dog has:

• A history of gastrointestinal sensitivity or pancreatitis
• Hemolytic anemia or predisposition to oxidant damage
• Known allergies or intolerances
• Access to tomato products containing garlic, onion, or excessive salt/fat

Sources and further reading

• ASPCA Animal Poison Control: Tomato (Solanum) plant toxicity guidance — https://www.aspca.org/pet-care/animal-poison-control
• American Veterinary Medical Association (AVMA) — plant and food toxicology resources
• USDA FoodData Central — nutrient composition of raw tomatoes
• Merck Veterinary Manual — toxicology and supportive care references

Key Takeaways

• CONDITIONAL: Ripe, red tomato flesh is generally safe as an occasional, low‑calorie treat for most dogs — avoid stems, leaves and unripe (green) tomatoes.
• Green tomatoes and plant parts contain solanine/tomatine and can cause GI and neurological signs — contact your vet or ASPCA Poison Control if ingested.
• Never feed tomato sauces, ketchup or pizza because of garlic/onion, salt, sugar and fat risks.
• Follow conservative serving sizes by weight and supervise small dogs with cherry tomatoes.

Frequently Asked Questions