The answer to if it’s advisable for your dog to eat tomatoes is not as straightforward as you may think and feeding your dog tomatoes can be a tricky business at best.
Although you may have heard of the health benefits of tomatoes, they also have some life-threatening risks associated with them, if you are not aware of some vital information regarding this fruit (didn’t know it was a fruit, did ya!?)
Can I feed my dog tomatoes?
The answer is, unfortunately, twofold – Yes and No!
While some parts of the tomato plant are good for your dog, others can be downright dangerous to feed him. In some rare cases, you will find that certain dog breeds are allergic  to tomatoes.
What benefits do tomatoes yield?
Tomatoes are packed full of nutritional benefits for both humans  and dogs, and if fed correctly to your pooch can supplement his diet to a large degree.
Lycopene  will help reduce the risks of strokes and heart disease. It also promotes healthy bones and aids in preventing cancer.
A precursor to Vitamin A, Beta-Carotene will improve cognition in your dog and ward off any metabolic syndromes.
An essential vitamin that will improve the immune system and reduce the risk of cardiovascular diseases.
Potassium in your dog’s diet will promote healthy nerves, muscles and blood pressure.
Aids with optimal eyesight. 
Fiber promotes a healthy digestive system.
Are tomatoes safe for my dog?
When it comes to tomatoes, it is essential to know which parts you can feed your dog, and which are the ones you should avoid. Parts of the tomato plant that should NEVER be offered to your dog include:
- immature green tomatoes. 
The reason for this is that these parts of the tomato contain high levels of a toxic substance known as tomatine.  Each of the above sections of the plant includes at least 5% of the tomatine substance, which is a dangerous amount for your dog to ingest.
Tomatine is a solanine poison  that is common in all plants of the nightshade family – including tomatoes.
Tomatine poisoning symptoms
Please note that the symptoms of a tomato allergy are different from the symptoms of tomatine poisoning.  If your dog has been exposed to the tomatine poison, you will probably notice the following signs:
- Tremors or convulsions
- Loss of coordination
- Muscle weakness
- Cardiac distress
- Severe gastrointestinal distress
- Dilated pupils
- Behavioral changes
It is vital to get your dog to your nearest veterinary clinic if you suspect he may have tomatine poisoning.
Do ripe tomatoes also contain tomatine?
Yes, ripe tomatoes do contain tomatine, but in minimal quantity, of which you will only find trace amounts of. This, therefore, makes the ripe tomatoes generally safer for dogs, but they should still be eaten in moderation. If you must feed your dog tomatoes, only do so occasionally.
However, to be on the safe side, you can opt to not feed your dog tomatoes. But in cases of accidental ingestion, it is reassuring to know that you are safe. In young pups whose immune systems are still developing it is safer to not feed them any tomatoes as all.
Wait, so are tomatoes good for dogs or not?
Well, the jury is still out on this. (Don’t forget there’s also apparently a big debate going on, as to whether tomatoes are vegetables or fruits . . .)
What the experts do agree on, however, is the fact that a tomato is very rich in nutrients.
This is because they are low in calories and high in fiber. You will also find large amounts of beta-carotene and carotenoids lycopene which are extremely useful in fighting diseases in both humans and dogs.
Also, tomatoes are rich in anti-oxidant vitamins such as:
- Vitamin B12
- Vitamin A, and
- Vitamin C.
… as well as minerals such as:
- Chromium, and
Is your dog an allergy sufferer? Consider these dog foods for allergies.
Can dogs be allergic to tomatoes?
Yes, some dogs can develop an allergic reaction to tomatoes, though it is not very common.
Unfortunately, there is no way of knowing beforehand, so it is advised to first give him a small amount and be on the lookout for any adverse reactions.
What are the allergy symptoms to look out for?
The following symptoms are likely to present themselves if your dog is allergic to tomatoes:
- itchy skin
- licking their feet
- skin rashes
- hot pink or red ears
- growling stomach
What about cherry tomatoes?
So long as they are red and ripe, you can give offer them to your dog. No variety of ripe tomatoes are actually off limits.
What about cooked tomatoes?
Yes. You can feed your dog cooked tomatoes.
Cooked tomatoes actually have the potent lycopene anti-oxidant in a simple form that the body can absorb quickly, so, it is a good idea to give your dog red ripe cooked tomatoes.
How many tomatoes should/can I give?
While there is no golden rule on how many tomatoes you can feed your dog, once you decide to introduce them to their diet, remember that moderation is key.
Do not give too many at once, because they will in all likelihood cause an adverse reaction.
As with most additions to a dog’s diet, always start very slow. Give one at a time and wait a few days to observe their reaction to the tomatoes. If he/she does not react negatively, then it is safe to give them tomatoes regularly.
Final thoughts on feeding dogs tomatoes
It is important to note that while tomatoes are not highly recommended, they do offer a wealth of benefits to your dog’s body. However, you must be very careful as stated above. In most cases, however, dogs will only eat tomatoes accidentally if you have a small tomato garden.
You can ensure they do not eat the unripe poisonous tomatoes from your garden by putting up a perimeter fence.
Other must reads:
- Can dogs eat bananas?
- Can dogs eat apples?
- Can dogs eat watermelon?
- Can dogs eat chocolate? Read before you feed!
- Can dogs eat pineapple?
- Can dogs eat strawberries?
- Can dogs eat oranges?
- Can dogs eat lettuce?
- “Oral allergy syndrome induced by tomato in a dog.” M. Fujimuri. K. Ohmori. K. Masuda. H. Tsujimoto. M. Sakaguchi. November 2002
- Kovalkovičová, Natália et al. “Some food toxic for pets” Interdisciplinary toxicology vol. 2,3 (2009): 169-76.
- Tomatine – PubChem
- “Solanine poisoning” British medical journal vol. 2,6203 (1979): 1458-9.
- “Tomatoes and cardiovascular health.” J.K. Willcox. G.L. Catignani. S. Lazarus. 2003
- Story, Erica N et al. “An update on the health effects of tomato lycopene” Annual review of food science and technology vol. 1 (2010): 189-210.
- Morris, Penelope J et al. “Safety evaluation of vitamin A in growing dogs” British journal of nutrition vol. 108,10 (2012): 1800-9.
- Dolan, Laurie C et al. “Naturally occurring food toxins” Toxins vol. 2,9 (2010): 2289-332.