06/21/2025
⚠️ Shocking increase in liver-damaging copper levels in labradors... are they linked to AAFCO change? Should you worry? 👀
This graph is taken from a study, published in 2018, that followed 546 labradors over a 34 year period (obviously not the same labradors!). 📈
The study found that copper in dogs’ livers increased dramatically over time – with very dangerous levels (over 1000 mg/g), that cause liver damage & cirrhosis, found much more commonly after the mid-1990s.
So what happened in the mid-90s?? 🤔
The study authors highlight that the stark increase comes after AAFCO’s 1997 change to copper requirements for commercial dog food. This required copper added to dog food be changed to a more bioavailable form. That is, one that your dog's body can more easily absorb from their food.
If you check the ingredients list on your dog's food, you can tell if it contains this bioavailable copper - it will say "copper sulfate," "copper proteinate" or "copper amino acid chelate." 🔎
The study authors say it's likely that increased "environmental copper exposure" is to blame for the dogs having more damaging levels of copper in their livers. They add that, "While causation cannot be determined, the close temporal association of changes …with changes in AAFCO copper supplementation recommendations are concerning."
In layperson's terms, the authors are worried that adding more bioavailable copper to dog foods, in accordance with the 1997 AAFCO change, might be the cause of the rise in damaging copper levels in the labrador livers.
So how worried should you be? 😳
According to Dr Pete of Voyager Dog Food Co., who is a leading expert in this area, some dogs can get rid of excess dietary copper. "You get the right dog, who can get rid of excess copper? Absolutely no big deal!" he says. But for other dogs - and labradors are a predisposed breed - excess dietary copper could build up in your dog's liver, causing damage & even early death. This is known as Copper Storage Disease. 🥼
This is a concern, because Dr Pete also says that this is often a "silent disease," that pet parents don't notice in their dogs until they've been "sick for a while." So too, the disease can only be full diagnosed with an expensive and intrusive liver biopsy (we're talking several thousand dollars, rather than "a couple of hundred bucks"). 💰
So, what can you do to protect your dog?
Importantly, don't panic. Remember what Dr Pete said about dogs who can get rid of excess copper? He said copper in their diet is "absolutely no big deal." However, if you're concerned that copper might be a problem for your dog, here are some suggestions:
1. Opt for dog foods that do not contain the bioavailable copper additives mentioned above. Check the label for 'copper sulfate,' 'copper proteinate' and 'copper amino acid chelate' and consider switching to a food without these additives under the guidance of your veterinarian. Be sure to check treats too! This is the first step - which will avoid adding more copper via your dog's diet.
2. If your dog has regular blood work done, keep an eye on ALT levels (this is a liver enzyme that goes up when your dog's liver is under stress). If the levels are rising, and especially if this is combined with weight loss or reduced appetite, and no other explanation of what might have caused liver damage, Dr Pete says it may be time to request a liver biopsy - this is the only way to diagnose Copper Storage Disease.
If a liver biopsy shows high amounts of copper, your vet may prescribe a copper binding medicine, like D-penacillamine, to help your dog's liver get rid of the excess copper.
With early treatment, many dogs with Copper Storage Disease recover and go on to life full and active lives.
3. If your dog has no signs and you're worried, a DNA test can reliably tell you whether your dog is predisposed to Copper Storage Disease, helping you to act before liver damage has occurred. We'll be doing more content on this shortly - keep your eyes peeled!
Got questions? We'd love to hear them - and if you comment, we'll reply. 💬
STUDY LINK HERE: 🔗 https://onlinelibrary.wiley.com/doi/10.1111/jvim.15308
