Liver is Toxic for Dogs?

Some recent misinformation

Spring has sprung!

It seems like every few months there is some new toxic food that people are worried about. Recently we have been seeing a lot of concerns about liver toxicity. So today we discuss the caveats and benefits of liver.

Before that here are this weeks recipes!

“My vet says liver made my dog sick…”

Even vets are not exempt from jumping to conclusions.

A video of a vet claiming that his dog got sick from eating too much beef liver has been circling the internet. He claims that liver is too high in copper and that it was affecting his dog’s health.

The challenge with drawing conclusions from one dog is that there is no way to compare results and know for sure what is causing a phenomenon. As we’ve discussed previously, mycotoxins in pet food, even in small amounts, are shown to affect liver function. There are also many other things that can affect liver function. This is why true scientists rely on randomized and controlled studies rather than anecdotal evidence to form conclusions. Even when a study shows a significant difference, researchers wait to form their conclusions until studies are replicated (confirmed) multiple times.

In a randomized controlled study, researchers can measure the exact amount of liver, copper and other nutrients and then compare those markers across a number of dogs. Many factors can cause issues in dogs, from environmental factors, to genetics, to food. RCTs are not foolproof, but currently they are best tool to examine whether a toxin or medicine has an effect on animals’ health.

This vet was irresponsible with his conclusions

Without a controlled study, it’s impossible to be sure of the exact cause of liver issues. According to researchers, some dogs are genetically predisposed to be copper sensitive, but commercial dog foods often exceed the recommended allowance.

Dog food is supplemented with everything that a dog needs to have, and usually in extra amounts called overages. Overages are added during manufacturing because many vitamins and minerals degrade over time, so manufactures add extra supplements to meet standards over their very long shelf life.

So when might liver be a problem?

For this reason, if a dog is fed a commercial diet or homemade food with a supplement, too much beef liver could be a problem. However, is this particular vet's dog having liver issues because of a genetic disorder, because of its food, or from copper in the liver? It’s impossible for us to know. This is why forming conclusions from limited evidence and then sharing them with others is foolish.

Dogs who eat commercially prepared food should not be eating a lot of liver, and they should not take supplemental minerals or vitamins at all. Their diets are supposed to be complete with all the vitamins and minerals they need. (Kibble’s macronutrients, however, are typically way out of line so omega-3s are still highly recommended.)

Real food is the antidote

For dogs eating home cooked meals, toxicity from liver, and whole foods in general, is rare. This is especially true if you are mixing up the recipes and feeding diverse meals as we recommend. Some vitamins and minerals in real food are more forgiving in high doses than synthetics. Sea kelp is one example that we’ve discussed. The iodine in sea kelp is less toxic per mg than the iodine from potassium iodide. Vitamins A, E, and B9 are also less toxic in their natural form. This is true of copper as well. Furthermore, liver is rich in cofactors like protein, zinc and B vitamins that regulate the absorption of copper. Nature is wonderfully balanced.

Benefits of liver

Some believe that liver contains toxins because it filters blood. Liver is actually a multipurpose organ that stores and makes glucose, regulates hormones, and synthesizes blood plasma amongst many others. The idea that it stores a lot of toxins is just not accurate. Toxins are filtered out of the blood and processed into less harmful substances, then eliminated via urine or bile (feces).

Liver, especially beef liver, is an extremely nutrient dense food. In addition to the nutrients mentioned above, beef liver is rich in selenium, vitamin A, vitamin K, vitamin E, and iron. This potent mix of nutrients helps to support a healthy immune system, improve skin and coat, as well as fuel energy production.

How often do we feed liver?

Sometimes we feed lots of liver, up to an ounce in a day. (They learned how catch with freeze dried liver treats.) Other times we might go a week or more without liver at all. On average they probably get about an ounce a week, but they could easily get less or more. It’s really not that complicated.

One meal with a lot of liver will not poison a dog. For the same reasons, several meals without liver or a few meals short on copper, zinc or any other micronutrient will not harm a dog either. Dogs evolved to store all essential nutrients in their bodies. They’ve lived for eons just eating whatever they could find. For some strange reason this has become a controversial take. But it should not be, it’s the way scavenger animals have been eating for all of history.

Nutrient restriction is good?

It’s true. There is a substantial body of evidence that suggests nutrient restriction is beneficial for animals. Specifically, caloric restriction (CR) is shown to extend average lifespan in mice, rats, monkeys, flies and worms. Additional benefits of CR include improved metabolic health and neuroprotective effects. Furthermore, nutrient stress triggers beneficial pathways including autophagy, AMPK, SIRT1 and others.

There are downsides to CR like lower muscle mass, and not all animals are affected the same. Some animals get very frail on low calorie diets, while a small percentage fare worse. However, the idea that dogs are super sensitive to natural nutrient deficiency or toxicity IS NOT supported by research. The benefits of this misinformation accrues to pet food manufacturers, “canine nutritionists” and others who want you to be reliant on them. Though we also sell food mixes, our intention is to help you with convenience, arm you with information, and hope that you will continue to support us. ❤️

That’s all for this week. Whether you celebrate Easter or not, We hope you had a great weekend!

All the best,

Joelle and The Precious Creatures Team