MSG, or monosodium glutamate, is well known as a flavor enhancer in Chinese restaurant food and a lot of packaged food products like canned soups and vegetables, processed meats, snacks like potato chips, salad dressings and frozen dinners.
But what about MSG for dogs? It may not be obvious, but there’s MSG in a lot of dog foods as well.
What Is MSG Or Vetsin?
MSG stands for monosodium glutamate. It’s a flavor enhancer derived from L-glutamic acid or glutamate, a natural amino acid that’s in foods like meat, fish, tomatoes, milk and mushrooms. Vetsin is another name for MSG in some countries, including the Philippines. Ajinomoto is another term for MSG.
MSG is a white, odorless, crystalline powder used in the food industry, also known as E621. It dissolves easily in water, separating into sodium and free glutamate. It’s popular in Asian cooking and packaged foods for its “umami” flavor that gives a meaty taste. But it’s not natural like L-glutamic acid or glutamate. It’s created through a fermentation process, and excess MSG isn’t excreted like excess glutamate would be.
The food industry claims that MSG is totally safe. And the US Food and Drug Administration (FDA) classifies MSG as GRAS (Generally Recognized As Safe). But still, quite a lot of people do experience unpleasant symptoms like headaches, flushing, sweating, nausea, heart palpitations, chest pain and facial numbness or tingling after eating food with MSG in it.
In people, MSG may also increase the risk of high cholesterol and triglycerides, obesity and diabetes … and it may lead to oxidative stress as well as liver and nervous system toxicity (1).
But your dog can’t tell you he has a headache after eating it.
MSG Alters Brain Response
MSG is used as a flavor enhancer … but, ironically, it’s actually quite tasteless itself. It works by tricking the brain into thinking food tastes good. It’s a type of neurotransmitter known as an excitotoxin, meaning it over-stimulates the brain, causing an overproduction of dopamine. This creates a brief sensation of wellbeing.
But it damages the brain and alters its ability to respond to the signal from the hormone leptin that tells us we’re full … which is why, when you eat foods containing MSG, you just want to keep eating, making the food seem almost addictive.
Of course, when it comes to dogs, most of them are greedy and just want to keep eating anyway … but if your dog’s eating kibble, MSG in his food might be increasing his seemingly endless hunger!
Is MSG Bad For Dogs?
It’s likely MSG is quite bad for dogs. And it’s scary to think that MSG might damage your dog’s brain.
Dr Russell Blaylock, author of “Excitotoxins: The Taste that Kills” says that it can cause brain damage (in humans) and may trigger or aggravate learning disabilities as well as diseases like Alzheimer’s, Parkinson’s, and Lou Gehrig’s.
Seizures In Dogs
Veterinarian nutritionist Dr Veneta Kozhuharova DVM, MRCVS, Cert.CFVHNUT (certified in Canine and Feline Veterinary Health Nutrition) has found that glutamate or MSG in dog foods can lead to seizures in dogs. She cites a study at London’s Department of Neurology, Institute of Psychiatry, finding that “Glutamate is the principal excitatory neurotransmitter in the brain and, as such, it inevitably plays a role in the initiation and spread of seizure activity” (2).
But that’s not all. Studies have shown other potential risks.
- A study in the 2008 Journal of Autoimmunity showed that injecting MSG into mice led to liver inflammation, along with obesity and Type 2 diabetes (3).
- Studies by Dr John Olney at Washington University using neonatal mice and varying injected doses of MSG found that the injections caused obesity, neuroendocrine disturbances, behavioral disturbances, as well as fetal brain damage in mice whose mothers who ate it when pregnant.
- Other studies in animals have shown that MSG is toxic to various organs such as the liver, brain, thymus, and kidneys.
And what’s worse, the effects accumulate over time. So if your dog eats food with MSG every day, it may take a while for the effects to show up.
Symptoms of MSG Poisoning In Dogs
While your dog’s unlikely to eat enough MSG or vetsin in his food to show acute signs of toxicity, be aware of some likely symptoms in case these develop over time. And if you keep MSG powder as a pantry item to flavor foods, make sure it’s in a dog-proof container or cabinet.
Signs your dog has had too much MSG include …
- Vomiting or diarrhea
- Thirst/drinking a lot
- Lack of coordination
- Seizures or tremors
How To Avoid MSG For Dogs
MSG can be in many dog foods, under various disguises. One of the pet food industry’s favorite forms of MSG is hydrolyzed protein, also used to enhance flavor. If you see “natural flavoring” or “digest” on the label, it’s probably hydrolyzed protein. It can also appear under other names, including:
- Any type of protein isolate (like soy protein isolate)
- Any type of textured protein (such as textured vegetable protein)
- Autolyzed yeast
- Hydrolyzed yeast
- Yeast extracts or yeast nutrient or yeast food
- Soy extracts
- Soy concentrate
- Sodium caseinate or calcium caseinate
- Disodium inosinate or disodium guanylate (which are flavor enhancers effective only in the presence of MSG)
- Monopotassium glutamate
- Glutamate, glutamic acid, or free glutamate
You may occasionally see it listed as MSG (monosodium glutamate)! But even if you’re a careful label reader, there are other ways your dog may be getting MSG in his diet.
MSG In Produce In Dog Food
There’s a product called AuxiGro that contains hydrolyzed proteins and monosodium glutamate. AuxiGro is used to increase crop yields and is sprayed on crops like lettuce (various types), broccoli, tomatoes, potatoes, peanuts, celery, cucumbers, navy and pinto beans; grapes; onions; bell, green and jalapeño peppers, strawberries and watermelons.
When vegetables and fruit start to spoil, they’re often used in pet foods and advertised as all natural healthy ingredients. There’s no way of knowing whether MSG is in the produce in dog foods.
MSG In Dairy Products
Processed free glutamic acid is in many dairy products like milk or cottage cheese, so if you add dairy to your dog’s diet, he may be getting some MSG that way too.
MSG In Coprophagia Products
If your dog’s a poop eater and you give him one of the products intended to prevent this behavior, beware … most of them contain some form of MSG, listed as monosodium glutamate, glutamic acid, or one of the other alternative names above. By the way, just about all of these products contain other undesirable chemical ingredients as well, so you might want to find another way to stop your dog’s poop eating habit. For example, one product is described like this:
“A convenient, easy-to-use roast beef flavored chew formulated with MSG and cellulose to assist in the breakdown of fiber, rendering the taste and texture of the stool unpleasant to eat.”
Cellulose is sawdust … so this product is sawdust flavored with MSG. And the manufacturer suggests you feed it to cats to stop your dog raiding the litter box!
Instead of commercial coprophagia products, give your dog a good digestive enzyme that’ll help him absorb nutrients better.
Avoid MSG With A Natural Diet
The best way to avoid MSG in your dog’s food is to feed a fresh, whole food, raw meat diet and avoid commercial, processed foods. Here’s an article to help you if you’d like to get your dog started on a raw diet.
- Hajihasani MM, Soheili V et al. Natural products as safeguards against monosodium glutamate-induced toxicity. Iran J Basic Med Sci. 2020;23(4):416-430.
- Meldrum BS. The role of glutamate in epilepsy and other CNS disorders. Neurology. 1994 Nov;44(11 Suppl 8):S14-23. PMID: 7970002.
- Nakanishi Y, Tsuneyama K et al. Monosodium glutamate (MSG): a villain and promoter of liver inflammation and dysplasia. J Autoimmun. 2008 Feb-Mar;30(1-2):42-50.