For more than a year, one word has dominated the canine nutrition world, creating confusion and concern among dog lovers. That word is taurine. Last year, the Food and Drug Administration (FDA) announced its investigation into increased veterinary reports of the heart condition dilated cardiomyopathy (DCM) in dogs consuming certain types of commercial diets. Some of these dogs also presented with low blood levels of taurine, a known cause of DCM in certain predisposed breeds, so it’s understandable that many people are concerned about dogs and taurine and the possible relationship between diet and taurine-deficiency DCM.
Today, I’d like to dive into the topic of dogs and taurine and why it’s important, as well as hopefully quell some of the confusion so that you can make calm, informed decisions as it relates to your dog’s health.
What is taurine?
Taurine is typically referred to as an amino acid, however it is not a traditional amino acid because it does not serve as a building block of protein, but rather is found abundantly in tissues and organs throughout, including the brain, heart, retina and muscles.
Taurine is considered a non-essential amino acid for dogs and adult humans because our bodies can synthesize it from the sulfur-containing amino acids methionine and cysteine in the presence of vitamin B6. Cats and babies cannot manufacture taurine, so for them it is an essential amino acid that must be obtained strictly from the diet.
Meat, eggs, and seafood are the richest sources of taurine.
Taurine is not found in plant foods.
Why is taurine important?
Taurine plays an important role in many biological and physiological processes, including producing bile salts necessary for fat digestion, regulating electrolytes in cells and balancing neurotransmitters in the brain.
Reported benefits include:
- Defends the liver against oxidation from free radicals
- Exerts anti-inflammatory effects
- Fights obesity
- Helps control diabetes and its complications
- Improves the body’s immune response
- Promotes reproductive health
- Protects the retinas and vision
- Reduces seizure symptoms
- Strengthens the heart muscle
- Supports healthy vascular function
Taurine and DCM in dogs
DCM in dogs is characterized by weakness of the heart muscle, leading to complications such as an enlarged heart and congestive heart failure, which can be fatal. Genetics is considered the greatest risk factor, with large and giant breeds including Doberman Pinschers, Great Danes, Newfoundlands, Boxers, Irish Wolfhounds and St. Bernards most susceptible. However, recently reported cases of DCM have risen and expanded to include other atypical breeds such as Golden Retrievers, Labrador Retrievers and even mixed breeds, prompting public concern and an FDA investigation.
Four of the atypical cases reported – three Golden Retrievers and one Labrador Retriever – presented with low whole blood levels of taurine. Four other atypical cases – a Miniature Schnauzer, a Shih Tzu and two Labrador Retrievers – had normal taurine levels.
Common among these recent cases regarding dogs and taurine is that the affected dogs consumed commercial foods listing potatoes or legumes as primary ingredients, which likely but not necessarily indicates a grain-free food because potatoes and/or legumes typically substitute for grain in commercial diets. The concern is that these grain-free diets are somehow causing low blood levels of taurine and resulting in taurine-deficiency DCM, even in breeds not normally predisposed.
We know that reports of DCM have risen in dogs consuming grain-free diets, however we don’t know why, and that is an important missing link. So, while we await further results of the FDA’s investigation, we need to be cautious about drawing “causation” from “trends.” The current information spreading online is leading to unwarranted public panic, as at this time there is no proof that grain-free diets are the culprit and there are many other possible factors that can come into play, including:
- Dietary chemicals
- Dog’s ability to process nutrients
- Dog’s health status
- Dog’s ability to synthesize and metabolize taurine
- Fiber content of diet
- Genetic predisposition
- Ingredient processing
- Interaction of ingredients
- Overall nutritional composition of diet
- Protein content of diet
A 2016 study published in the Journal of Animal Science and Technology found that beet pulp, a common ingredient in dog foods, decreased taurine levels in dogs by increasing the amounts of bile acids that were excreted in the feces and by decreasing overall protein digestibility. Since the amino acids methionine and cysteine are needed to synthesize taurine, decreased protein digestibility would reduce their availability and could result in taurine deficiency. This does not mean that beet pulp is the only culprit in these most recent cases, however it is one of many possibilities that warrants further investigation.
Should you supplement with taurine?
I strongly urge that when you feed your dog a plant-based diet, you supplement with taurine.
Decades ago, prior to understanding taurine’s role in heart health, commercial vegan diets did not typically include it, resulting in unnecessary cases of DCM in dogs consuming these diets. Now, reputable vegan diets include taurine, so be sure to carefully check labels. I only recommend commercial vegan foods that are supplemented with taurine, which shows that the manufacturer understands this issue.
If you are home-preparing your dog’s vegan meals, you should add a taurine supplement daily.
There is no set dosing for taurine and dogs. According to holistic veterinarian Dr. Jean Hofve, “If one is feeding a potentially taurine-deficient food, it would be a good idea to give supplemental taurine at up to 1000 mg per day for every 40 pounds of the dog’s body weight. Taurine, which usually comes in capsules of 500 or 1000 mg, is very safe even at extremely high doses. It has very little taste; and is relatively easy to give.”
I recommend dividing the dose between a.m. and p.m.
The new incidences of DCM in dogs certainly warrants further investigation, however it is far too soon to draw any conclusions as to causality or to take action based on blind panic.
I also get asked a lot if its unsafe to feed a grain-free diet. I am not “anti-grain” at all, however if a dog does well on a grain-free diet, at this time I see no reason to change it.
This article is modified from my article that originally appeared in my Chow Time column in the Feb-March issue of Dogster Magazine.