Should Dogs Eat a Vegan Diet?

Golden Cali watches puppy Orly bite an ice cream cone
A decidedly non-vegan treat!

A friend recently shared with me an article about feeding dogs a vegan diet. The article referred to two studies done in the UK with the same lead researcher. The upshot is that these articles say that dogs can live healthy lives on a vegan diet and that they find vegan diets palatable. In fact they claim that “vegan pet foods are generally at least (emphasis added) as palatable to dogs and cats as conventional meat or raw meat diets, and do not compromise their welfare.”

Color me skeptical. But I’m willing to consider the evidence.

Both studies were published by PLoS One (Public Library of Science), which means they are freely available:

The first issue with these studies is evident from their titles: Both are based on an online survey of dog and cat owners. The ‘indicators of health’ paper used a subset of the data used in the palatability study. Using a self-selected group of pet owners answering an online survey is not a scientifically sound method, and there’s no way to know whether the responses are accurate.

The questions are also problematic. To gauge dogs’ health, for example, they asked the owners to give their opinion of their dog’s health — and to also guess what their vet would say about their dog’s overall health … even for dogs whose owners report not having taken them to a vet in over a year (or ever).

There are other issues with the questions, such as the limited response choices for the kind of diet a dog ate — “conventional” meat-based, which covers an enormous variety of foods; raw, which could be homemade or commercial; and vegan, which also could be homemade or commercial — and not accounting for treats. A combination wasn’t an option, but I — and many people I know — feed some raw and some kibble.

Based on their data, though, the authors are certain that they know that dogs both enjoy their vegan diets and are generally perfectly healthy while eating vegan. (I haven’t seen a study on whether the cats on vegan diets were healthy … but it’s trickier with cats.)

I’m still very skeptical.

I actually do think that dogs can be healthy on a vegan diet, but it’s not easy. I think that, for an active dog, it would be challenging to provide sufficient protein from sources that dogs can easily digest without feeding so many carbs that the dog would become obese. (The study authors never actually saw the dogs, so we don’t know if the vegan-fed dogs were healthy weights.)

But what I am really skeptical of is the claim that the dogs (& cats) found the vegan diets “at least” as palatable as a meat-based diet. I simply do not think that dogs (or cats) want to be vegan.

As any trainer knows, some treats are “higher-value” than others.

While each individual dog will have different preferences, the highest-value treats tend to be the ones that are closer to fresh: fresh meat, fresh fish, cheese, even some fresh veggies. A close second is “jerky” type treats — dried meat or fish — or the soft treats. These smell and feel more like meat, and they probably taste more meaty (or fishy). Low-value treats are biscuit-type treats — cookies, kibble, Charlee Bears. These are hard and dry. They’re nicely crunchy, but I doubt they taste like much.

Within my dogs’ varied diet, they have favorite foods. Their behavior is very different when I am preparing them fresh food or mixing in canned sardines with their kibble than if I’m giving them plain kibble.

But they’re golden retrievers, so they greet any and all food eagerly, exhibiting some behaviors described in the study as indicating palatability and enjoyment, such as eating quickly, wagging their tails, and licking the bowl or their lips. Even non-golden-retrievers tend to eat quickly in multi-dog households, so this is not necessarily an indication that the dog likes the food.

Some of the other behaviors listed as indicating palatability are … at best, questionable. They’re also behaviors that I would not tolerate, no matter what they meant. These include vocalizing for food, stealing food, raiding food bins, waking the owner during the night for food, showing aggression around food, or staying near the food bowl. The last two indicate resource guarding, a whole separate problem that has nothing to do with the taste of the food.

The authors also say that the fact that the dogs ate the food they were served means that the food was palatable to them. But it could just mean that the dogs were hungry and knew that they weren’t getting a menu to choose their dinner from.

Or maybe it meant that the dogs were hungry because their vegan or kibble-only diet wasn’t satisfying. How do the authors know that the vocalizing dogs were asking for food? Or for more of the same food? Maybe they were literally crying for better food? And, how many dogs wake their owners up at night because they love their dinner so much they want more? Is that a thing?! Or were these dogs so hungry they couldn’t sleep?! Or they heard a strange noise or they were scared by the thunder or just wanted to cuddle …?

(In case you’re still wondering, I am pretty sure that the the study does not show what the study authors say it does.)

I’m also pretty sure that my dogs don’t want to be vegan.

To be fair, I am strongly in favor of a vegan diet. I am not vegan, but I inch closer to that ideal all the time. I also agree with the authors’ statements about the unsustainability of the way we feed pets. The whole food animal industry is unsustainable (and, I believe, problematic in so, so many ways).

Cali's pawprint looks like a smiley face
Cali’s pawprint; she’s a very happy girl

So, finally, we get to the real dilemma: Should I work toward my dogs’ happiness by feeding them a diet they enjoy and thrive on? Or should I follow the study authors’ ideals, which I share, of seeking a more sustainable option?

Cali and Orly vote for happiness.

Don’t Get Ripped Off!

Many years ago, when I started giving Jana glucosamine supplements, I carefully reviewed all of the special products formulated for dogs, finally choosing one that my vet recommended. Over the years, I have given my dogs many dietary supplements, such as (not all at once):

  • Glucosamine / joint support
  • Fish oil
  • Green-lipped mussel
  • Probiotics
  • Digestive enzymes
  • Vitamin E
  • CBD
  • Pumpkin
  • Yogurt / kefir
  • Sardines

All of these are things that some people use for similar reasons — to enhance their digestion, reduce inflammation or aches, improve overall health. But do you need to get special products for dogs? Not always, though the line can be fuzzy.

Glucosamine, CBD, probiotics, digestive enzymes, and vitamin E are not things that I would generally eat for dinner. I might use them if I thought they’d help resolve an issue, like painful joints or an upset stomach. Can Cali share mine?

I’m not an expert in canine digestion, but I suspect that the doggy digestive tract and microbiome are quite different from their human equivalents. So when I have selected digestive enzymes and probiotics for my dogs, I have used canine-formulated products. I use a canine joint support powder, too, though that is primarily because it’s easy and inexpensive. I mix together a joint supplement, a digestive enhancer, and extra turmeric and scoop a little onto each meal.

But for many dietary supplements, and especially things like fish oil, sardines, or pumpkin — there is absolutely no difference between the “canine” and human products; the human product might even meet higher production or safety standards — and cost a lot less.

Buying 100% pumpkin puree “for dogs” is just silly, for example. As long as you get the puree, not the pumpkin pie filling, there’s no difference. Same with fish oil or sardines, though those dried ones are handy as treats (if you can stand the smell).

If you watch the dosage, you can use green-lipped mussel (powdered) and vitamin E sold for humans; I do, and have safely done so for years. I’ve used generic Immodium and Pepto Bismol and Prilosec for dogs (& humans) as well. And I know many people who do the same with CBD oil, though for edibles … I stick with the doggy ones; no CBD gummy bears for Cali

A lot of foods that are healthful and beneficial for humans are also great treats for dogs: Eggs, fish, fish oil, pumpkin, Greek yogurt (plain) or kefir, peanut butter, many raw vegetables and fruits. As long as there’s no added sugar and absolutely no xylitol, your dog can safely enjoy small amounts of these foods. Cali would add ice cream and pizza crust to this list.

Don’t fall for the marketing and reach for the puppy pumpkin! Instead, share a healthful treat that you and your dogs can all enjoy together.

Cali plucks ripe berries from a mixed cluster, leaving green ones behind
Some fresh-picked raspberries perhaps?

Hidden Poison: Xylitol and Dogs

I recently read the ASPCA’s list of the toxins most commonly ingested by pets: Announcing the Top Pet Toxins of 2015. I thought it was worth sharing.

I’d rank them differently, though. The top two they list are medications (prescription and over-the-counter). While I don’t doubt that these cause many problems for pets, I also think that most of you, my readers, know to keep your meds out of pets’ reach.

Number four on the ASPCA list is where I want to focus this post — in particular, an item included under number four: Xylitol.

Xylitol is a sweetener. According to xylitol’s official website, “Xylitol is a naturally occurring carbohydrate, that looks and tastes just like regular table sugar. It is a natural sweetener that can be extracted from any woody fibrous plant material.” Who knew?

It’s perfectly safe (as far as we know …) for humans. The problem is, xylitol is highly toxic to dogs. Even a small amount can cause liver toxicity or severe hypoglycemia. It triggers the body to release insulin. Only a tiny amount — a tenth of a gram per kilo of dog’s body weight (a 60-lb. golden, Jana for instance, weighs about 27 kilos) can cause severe hypoglycemia in a dog. Keep in mind that one packet of the sweetener, what you might add to your morning coffee, has more than a gram.

When it was first introduced, xylitol showed up in things like toothpaste and mouthwash. Then it became common in mints and chewing gum — things that most people don’t share with their dogs. Now, though, xylitol has taken off as a sugar substitute for people with diabetes. It is appearing in baked goods, ice cream, even peanut butter. I give my dogs peanut butter every time one of them needs a pill (do you seriously think I can give the pill recipient some peanut butter and not give any to the other dog?). I buy natural, nothing-added-but-salt peanut butter, but … hearing that xylitol might be in peanut butter really brought home to me how essential it is to check the ingredients list, especially on anything that is “sugar free.”

Xylitol is even more dangerous than chocolate, according to this detailed article on Preventive Vet’s website: “Xylitol: The ‘sugar-free’ sweetener your dog NEEDS you to know about.” The article provides illustrations showing how much gum or sweetener powder would add up to a dangerous dose for different-sized dogs. Preventive Vet also has this list of grocery products that contain xylitol.

Symptoms of xylitol poisoning include vomiting, weakness, lack of coordination, lethargy, tremors and seizures. However, your dog’s chances of recovery are much better if you start treatment before he shows symptoms, so if you suspect that your dog ate something with xylitol, get to a vet immediately.

Better than treatment, of course, is prevention. Read the labels of products you buy and keep anything with xylitol out of your dog’s reach. If your dog sometimes gets into your purse or that niche in the car where you keep a pack of gum, don’t take chances; buy products that don’t have xylitol.

Some Like It Hot

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When Jana was a young puppy, she had the strange and (I thought) disgusting habit of shredding, and sometimes eating, the trash. If I left her at home for too long — which, when she was a few months old meant “more than 10 minutes” — she’d empty one or more wastebaskets, usually leaving some of the shredded remains next to the wastebasket. Ick.

I knew that buying wastebaskets with lids or placing the wastebaskets out of reach would manage the problem, but I wanted to stop the behavior. A more-experienced trainer friend had a suggestion: douse the contents of the trash baskets with something very hot or spicy, something that would repel her with its scent or, if that failed, with the first bite. Tabasco sauce, perhaps.

Despite being a bit dubious, I decided to try it out.  The next time I was leaving Jana at home, I liberally sprinkled Tabasco over the crumpled tissues and bits of paper in the wastebaskets. I returned home to a floor clear of shreds … and to empty wastebaskets and a happy dog, wagging her thanks. “Great sauce, Mom, can I have some more?”

Hmmm. Not the reaction I had hoped for.

She’s consistent in her taste, though. Her dad, Moshe, used to give her bits of pita with hummus and schug, a very hot Yemenite condiment that makes smoke come out of my ears with the merest whiff. She now enjoys her breakfasts and dinner with a healthy spoonful of turmeric (a great anti-inflammatory).

I ascribed Jana’s odd penchant for spicy food to her Israeli heritage. Until last week.

We’ve been spending lots of time at the home of Gracie and Scarlett, two Montana goldens whose dad has a beautiful garden. The garden currently is bursting with an abundance of tomatoes, beans, squash and peppers (to Cali’s dismay, the peas are done for the season). Among the peppers that Deni harvested a few days ago were dozens of beautiful jalapeños.

As is her habit, Scarlett (now eight months old) watched like a hawk as Deni harvested and sorted vegetables, pouncing on any that fell to the ground and, when the opportunity presented itself, snatching veggies off the table. Green beans, squash, tomatoes … fine. Then she nabbed a large jalapeño and ran off to her “hiding” spot under the deck. As Deni watched in amazement, Scarlett took a bite, then another and another — until she had eaten the entire jalapeño, seeds, ribs, and all. As if to prove that she can take the heat, she nabbed another the next day and ate it, too. She has not shown any sign of ill effects or even indigestion. She didn’t even gulp down an entire bucketful of water afterward (as I would have).

While I certainly do not advocate feeding spicy foods to dogs, it seems that Jana is not the only girl who’s looking to spice up her kibble, fish, and peanut-butter cookie diet. Who knows? If your dog is turning her nose up at her ordinary meals, perhaps the problem isn’t that she doesn’t like the food — she might just be holding out for the right condiments.

(In case you’re wondering: Jana (mostly)outgrew her trashy habit; now she only shreds one tissue and leaves it for me, and only if she’s angry.)

Food Before Thought


As Deni and Albee prepared to head off to a Rally Obedience class the other night, we discussed when to feed the dogs their dinner. Many trainers over the years have advised their human students not to feed dogs before training class. The dogs work better when they are hungry, is the claim. Deni and I pondered this, wondering whether it was good advice, anthropomorphism gone amok, or just plain silliness.

If it is an attempt to look at dogs through human eyes (the anthropomorphism gone amok theory), I guess it can be argued that really wanting something might make a being focus harder on what he or she has to do to get it. Therefore, if the dog really, really wants food, wouldn’t the dog focus harder on figuring out how to get it? Might sound plausible … except for a few problems. One is that the tiny tidbits of food a dog gets as rewards in training hardly take the place of a meal. And, this theory demands that you ignore stacks and stacks of research about learning or concentration and hunger.

Kids do not learn well when they are hungry. A really hungry child, and, probably, a really hungry dog, simply does not focus well. Research showing this has led public schools in low-income areas to offer not only free lunches, but breakfast as well, in attempts to boost concentration and improve kids’ learning.

Adults’ performance also suffers if we don’t eat a healthful breakfast. We know this, yet somehow think that our dogs will focus and learn if they are hungry? Doubtful.

Some trainers make a comparison with human athletes and point out that athletes are unlikely to eat a large meal just before a workout. Sure, but if training class is at 7 p.m., that is not a valid argument against feeding the dog at 5. Anyhow, a Rally class, an obedience class, even an agility class has a lot more in common with a grade-school classroom or a desk job than a triathalon. The dogs are not asked to perform athletic feats for hours, or even minutes on end. They are asked to pay attention to their handlers, to ignore distractions, to figure out what is needed, whether it is touching the contact at the end of the dog walk, sitting and staying for three minutes, or walking on a loose leash. The demands are primarily mental.

But there’s another, more important element. When trainers talk about training, it’s hard to avoid mention of the four quadrants of operant conditioning / behaviorism. The positive reinforcement quadrant is the one we are most familiar with — rewarding behavior we like. Ostensibly, the advice to train hungry dogs ties in with this: The dogs will get food rewards for their performance, and better performance will lead to more rewards. It’s all good, right?

Let’s look at it more honestly. Depriving a being of something it needs in order to get it to do what you want is called … torture. Withholding meals, then providing minute rewards for compliance falls into the “negative reinforcement” quadrant — removing a negative when the dog performs the requested behavior is supposed to increase the likelihood of the dog performing the behavior. Late dinner is about as negative as it gets for some dogs!

I know that comparing delaying a meal with common negative reinforcement techniques like ear pinch is an exaggeration. But comparing dog training class to an athletic workout isn’t? The dog will (eventually) get a meal, so feeding after training is not really abusive. But it is unfair. And it exploits the complete control we humans have over every aspect of our dogs’ lives.

The advice to delay meals might have been conceived by trainers who worked with dogs that are less food-obsessed than golden and Labrador retrievers. I still think it is wrong. A meal and tiny little training rewards are not the same thing. If your dog is unwilling to work for the training rewards you are offering, it is not because you have fed him; it is because the rewards you are offering are not, in that dog’s mind, motivators.

The cardinal rule of any kind of motivational training is that the trainee — the dog — determines what a motivator is and therefore what the reward should be.

If your training treats only motivate your dog when he is ravenous, skipping dinner is not the answer. Try using better treats. Try using a tennis ball, a tug toy — anything that your dog loves — as a reward. I might be willing to work for several hours to earn a paycheck that will arrive next week, but Cali, Jana, and Albee will always choose the freeze-dried liver over the cash — and they want it now, please. In fact, they will choose liver over and over again, at every opportunity, regardless of whether they’ve had dinner.