It seems everyone has an opinion on the secret to living longer these days, but now science suggests that taurine might be part of the answer. Recent studies have shown that taurine supplements can extend the longevity of lab animals, giving researchers hope that it could have direct benefits for our vitality as well. However, humans aren’t the only ones in the house who need this basic amino acid to stay fit and healthy.

Dogs similarly require taurine to stave off disease and promote proper brain and heart function. As with many critical nutrients, dogs depend on their diet to maintain appropriate levels, putting the onus on owners to ensure their pets receive balanced nutrition.

Is your dog eating healthy? We’ll find out in this look at taurine in dog food, why it’s necessary, and what could happen if your furry friend isn’t getting enough.

How Does It Work?

The interesting thing about taurine is that although dogs depend on their diet to keep their blood taurine levels up, dog food doesn’t have to contain any of this vital amino acid. Unlike cats, dogs can synthesize taurine from other dietary sulfur amino acids.

If they receive adequate amounts of methionine (one of the ten essential amino acids for dogs) or cysteine, their liver and central nervous system can produce taurine via enzymes in the transsulfuration pathway.

What Does Taurine Do?

Once synthesized, taurine has several critical functions in maintaining a dog’s homeostasis. It aids in preventing taurine-deficiency diseases and moderating numerous bodily functions, including those of the eye, immune system, nervous system, heart, and brain. The following are some of the essential actions taurine is involved in:

What Happens If Your Dog Doesn’t Get Enough Taurine?

Given its diverse roles throughout the body, a lack of taurine or amino acid precursors in a dog’s diet can have severe implications for their health. Potential issues taurine deficiency could cause include:

Dilated Cardiomyopathy

Much of the research on taurine in dog food has focused on how it affects dilated cardiomyopathy (DCM). Although the exact relationship isn’t clear, studies have found links between taurine deficiency and increases in DCM among dogs without a genetic predisposition to the condition.

Dilated cardiomyopathy is a form of heart disease in dogs. Thinning of the muscle weakens the heart, reducing its ability to pump blood. DCM can occur due to a primary abnormality of the heart muscle itself, but it can also be seen secondary to diet, abnormal heart rhythms and infectious or metabolic causes. Signs of DCM include:

DCM signs can appear slowly or suddenly. Vets can catch it before signs appear by identifying arrhythmias or heart murmurs. When it progresses to congestive heart failure, the prognosis worsens, and the dog faces a higher risk of death.

Dilated Cardiomyopathy and Taurine Deficiency

Taurine deficiency is one of the nutrition-related reasons dogs may develop secondary dilated cardiomyopathy. Some breeds, including American Cocker Spaniels, Golden Retrievers, Portuguese water dogs, and Newfoundlands, have shown predispositions for taurine deficiency.

Older dogs are more prone to lower taurine concentrations, as are large dogs that synthesize taurine at a lower rate than smaller breeds. Not all dogs develop DCM from taurine deficiency. In those that do, diet changes and taurine supplements can often reverse the condition.

Diet and Taurine Deficiency

Taurine deficiencies due to diet can occur through a lack of amino acid precursors in the food or decreased bioavailability and digestion. Plants contain little to no taurine. Studies in the late 1990s/early 2000s found links between taurine deficiency and lamb meal, rice bran, and whole grain rice in dog foods. Later research indicated beet pulp fibers can substantially decrease taurine status. Generally, high-fiber diets have an apparent connection to taurine depletion.

Preparation methods can also affect taurine levels. Taurine is highly soluble in water. Water-based processes like boiling or basting increase taurine loss in taurine-rich foods while feeding meat raw, frying it, and baking it retain more of it.

Grain-Free Diets and Taurine

In 2018, the FDA began investigating grain-free dog foods and their connection to increased cases of DCM. Over 90% of reported cases involved dogs fed grain-free diets. Potatoes and pulse (legume seeds), like peas and lentils, are heavily featured in these foods.

Legumes have limited sulfur amino acids to contribute to taurine synthesis. One concern was that, despite high amounts of overall protein in these diets, they didn’t supply dogs with enough taurine or precursor amino acids.

A 2018 study on Golden Retrievers supported as much, finding that 23 of 24 dogs on a grain-free, legume-rich diet had a taurine deficiency that resolved after a diet change and supplementation. However, among recent research, the study is an outlier. Despite the connection to DCM, additional research shows these diets likely have a more complicated effect on taurine levels.

Taurine, Digestibility, and Bioavailability

Several studies have found no differences in plasma or whole blood taurine concentrations between dogs on grain-free and grain-based diets. Part of this may be due to taurine deficiency occurring elsewhere. Taurine is one of the heart’s most abundant free amino acids, and some suggest normal levels in plasma and blood may not reveal deficiencies in muscle tissue.

Alternatively, complex interactions could affect taurine’s metabolism. Anti-nutritional aspects and high levels of soluble fiber in legume-rich foods might contribute to changes in gut microbiota and taurine loss through fermentation and fecal bile acid excretions.

While many grain-free foods have taurine and amino acid precursors similar to traditional diets, these dietary factors, paired with the dog’s genetics and metabolism, could impede digestibility, absorption, and bioavailability.

Other Causes of Taurine Deficiency

Outside of diet, cystinuria may cause a taurine deficiency. The hereditary condition causes cysteine to build in urine and form stones rather than reabsorb into the kidney. Signs of cystinuria include difficulty eliminating and blood in the dog’s urine.

A lack of specific vitamins can also affect taurine synthesis. Vitamins B6 and B12, zinc, and magnesium are co-factors in the transsulfuration pathway and cardiac metabolism, making them essential in maintaining amino acid levels.

Which Foods Have the Most Taurine?

Animal tissues contain the highest levels of taurine and its precursors, methionine and cysteine. Dark chicken meat and organ meats, such as heart, are notably high in taurine. Other sources of sulfur amino acids include:

Frequently Asked Questions (FAQ)

How Do Vets Test for Taurine Deficiency?

The signs that may be seen with a taurine deficiency, including panting, weakness, collapse, painful or bloody urination and abdominal pain, can be seen in many other conditions. If you’re concerned about the impact of your dog’s diet on their taurine levels, your vet is the best resource for examining your dog, analyzing their diet and running appropriate tests.

Bloodwork can measure your dog’s circulating taurine levels if necessary. If DCM is a concern, your vet will listen to the heart. Any abnormalities in heart rhythm or rate may require additional tests, including EKGs or echocardiograms, to monitor the heart’s structure and performance.

How Can You Ensure Your Dog Is Getting Enough Taurine?

Unless your vet has your dog on a unique diet, switching to traditional complete dog food with high-quality animal protein as its top ingredient is an excellent first step in keeping your dog’s taurine levels up. Read food labels, get the best food for your dog’s size and life stage, and follow the feeding directions.

Should your vet determine your dog has low taurine, or they have DCM or other heart disease, they may recommend supplementation and/or a diet change. Taurine supplements are available in powders, pills, and liquids. Dogs tolerate taurine well, so there’s little risk of an overdose.

Your vet will likely schedule follow-ups to monitor the taurine levels after treatment. For more information on creating a balanced diet for your dog, you can consult a veterinary nutritionist.

Conclusion

Taurine is rarely the first ingredient we consider when choosing dog food, dogs can synthesize it so it is not considered an essential amino acid as it is in cats. However, it is essential that a dog’s diet contains adequate amounts of taurine or the precursors needed for synthesis. Maintaining an adequate supply has implications for our dogs’ health, helping them avoid serious health conditions while improving their quality of life. Predisposed breeds may have altered taurine metabolism and requirements. Consider your dog’s daily diet and talk to your vet about how taurine in dog food could benefit your pet.

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