Beyond Taurine Supplementation

After reading “taurine” in our title did you think this post would cover the ongoing debate about dilated cardiomyopathy (DCM) in dogs? No; not directly. Sydney Banton, Julia Pezzali, Anna K Shoveller and their colleagues – all predominantly at the University of Guelph – never once mention the phrase in their latest published study despite having previously completed some of the best research surrounding the topic. We surmise that they believe the DCM topic was becoming all-consuming and even myopic. Time to move on and assess the big picture! 

Yes; DCM is a very complex disease, but taurine deficiency is only one potential cause of a disease that can be multifactorial. Erroneous rushes to treat DCM may, in fact, exacerbate or cause another disease. Bear in mind, that taurine supplementation is not considered harmful. 

We imagine this research group surveilling the box of the body, seeing what they can add without overfilling it and disrupting its balance, and notating the intensely complicated interactions of vitamins, minerals, and – in particular – amino acids. 

We digress. 

So, what did this group do? They compared three different supplementations: creatine-carnitine-choline; standalone taurine; standalone methionine; and, a control with no supplementation. On day seven, they took a fasted blood sample before they fed the dogs, and then collected blood samples at nine different intervals for six hours to find out the effects of these supplements on the bloodwork in dogs. 

Need-to Knows for This Post

Essential Amino Acid – An essential amino acid is one that cannot be produced by the body, is necessary for its functioning, and must be ingested. The other amino acids can be produced by the body, but sometimes can be used or needed as additional supplementation. These are called nonessential simply because the body can produce it. They are still special and important. Plus, the body might need a little boost of these as well. 

Methionine – Essential amino acid

Arginine – Essential amino acid 

Lysine – Essential amino acid

Glycine – Nonessential amino acid 

Cysteine – Nonessential amino acid 

Methionine + adenosine triphosphate = S-adenosylmethionine  (SAM or SAMe). You’ll know SAMe from the supplement aisle in your local store. 

Creatine – Nonessential amino acid created through several chemical reactions involving glycine, arginine, and SAM. Creatine is stored in the muscles and is used for energy. It may also play a role in regulating neurological diseases and plaque buildup in the lining of arteries.

Carnitine – Nonessential amino acid that is created using SAM and lysine. Helps with energy production. 

Taurine – Nonessential amino acid that is biosynthesized by SAM and cysteine that helps with important functions in the heart and brain, as well as promotes nerve growth. 

Homocysteine – Homocysteine is a byproduct (waste) of SAM. Homocysteine can be good because the body can recycle it back into methionine or convert it into cysteine with vitamin B. However, high levels of homocysteine have been found in dogs diagnosed with myxomatous mitral valve disease (MMVD), which is a relatively common type of congenital heart disease in dogs. 

Choline – Choline is not a vitamin nor a mineral. It is an essential nutrient and a methyl donor that helps recycle the methionine from homocysteine. 

What are their hypotheses?

Supplementation of creatine, carnitine, and choline in grain-free diets may play a role in sparing the methionine requirement without increasing homocysteine concentrations. Supplementing these nutrients could also aid in the treatment of disease that causes metabolic or oxidative stress, including cardiac disease in dogs.

We hypothesize that dogs supplemented with creatine, carnitine and choline will have greater postprandial plasma creatine and creatinine concentrations compared to dogs fed methionine, taurine and the control.

Addressing Core Issues

In their paper published in November 2022, they focused on creatine. They have previously reported the findings of the methionine and taurine supplementation. We will review the results of those, and find the creatine work especially intriguing. We are also looking forward to reading their new work regarding carnitine and choline supplementation. 

#1. Pulse ingredients (legumes) are often used to replace grains to bind grain-free kibble diets. Pulse ingredients are lower in cysteine and methionine, but have high concentrations of lysine. 

#2. The heat processing to create kibble degrades the creatine in animal protein to creatinine. The body has no purpose for creatinine so it is filtered through the kidneys. 

#3. When creatine is created in the body, it uses the most methyl groups from SAM. By the way, carnitine uses a lot too. 

#4. Creatinine in blood is an indicator for kidney disease. 

#5. Human studies suggest that supplementing with creatine decreases homocysteine concentrations. 

#6. Establishing a reference range for creatine levels in dogs.

Methionine Supplementation

On the surface, we all might think that adding methionine or SAM will do the trick since it is the backbone to all of these necessary reactions. 

However, the University of Guelph researchers found that dogs supplemented with methionine had elevated plasma homocysteine, as well as plasma and whole blood methionine concentrations at hour 1 and at hour 6 after eating, compared to dogs fed the control, taurine-supplemented, or creatine-carnitine-choline formulae. 

Taurine Supplementation

The important question on every mind!  

Whole blood taurine tended to be higher in the methionine and taurine groups compared to creatine-carnitine-choline. 

Thus far, the results reported have been fairly predictable, which reassures us that this research has a valid scientific basis.

We speculate that the choline is at work in the creatine-carnitine-choline supplementation because of the finding that plasma taurine was higher in all three supplemented groups compared to the dogs in the control group.

Creatine in the Creatine-Carnitine-Choline Supplementation

As anticipated, plasma creatine and creatinine were higher in dogs fed the creatine-carnitine-choline supplementation compared to the other two supplementations and the control. 

It is interesting to see the spikes and drops of creatine and creatinine at each of the nine time intervals between the diets. 

Fasted plasma creatine was about the same but a bit higher for the creatine-carnitine-choline supplementation group compared to the taurine and the control. Methionine supplementation was the lowest. At the hour 6 check, it did decrease but remained elevated compared to the others. 

Fasted plasma creatinine between all groups was about equal. While the creatine-carnitine-choline supplement generated the highest spikes in plasma creatinine post-meal, the other three also caused plasma creatinine to rise above the established serum reference range for mixed breeds and the research team’s plasma creatinine reference range. By hour 6, the creatine-carnitine-choline group still remained a little elevated in plasma creatinine compared to the other diets, but had pretty much leveled out with the rest. This is an excellent reminder that creatinine should always be measured after fasting, and the parameters of exercise, supplements and food should be taken into account. 

The team did not see a decrease in homocysteine and methionine levels when the food was dressed with creatine-carnitine-choline supplementation. We believe the team expected this to occur.  

Some people reading this may think the researchers’ potential reasons why the reduction of homocysteine did not occur as excuses. We do not. They are looking at the bigger picture and take into consideration factors known to trigger homocysteine reduction by creatine.

One of their postulations is that creatine may reduce oxidative stress markers induced by exercise. The study dogs were not exercise challenged as that was not in the scope of the study. Additionally, the control diet exceeded amino acid requirements at maintenance. So, the abundance of amino acids in the control diet plus the lack of additional exercise bypassed any sparing effect creatine may have supplied. 


Please do not start adding creatine-carnitine-choline to your companion dog’s food at this time. Many caveats exist with this project such as the dogs were all beagles and adults. The team noted that different breeds, puppies, and dogs engaged at various levels of activity may have other requirements. 

Plus, this is a very specific food: grain-free, kibble. We know that raw diets and less processed diets have higher levels of creatine. 

Our goals were to simply illustrate the diet sparing effects, diagnostic factors, nutrition, lifestyle, and balance involved. For example, instead of throwing additional methionine at a problem that might cause another problem such as homocysteine, perhaps we should increase creatine so that the methionine can be used somewhere else in the body. Yet, creatine levels have to be balanced so that kidney disease does not occur. Then again, we have to make sure creatinine testing is occurring at the right time. 

Once the carnitine and choline results are released, we will be sharing those with you. 

In another one of our upcoming blog posts, we will be discussing reference ranges of amino acids. Is it time for an adjustment of these numbers and are they relevant to the diagnosis of cardiac disorders? 


Banton, Sydney et al. “83 The acute effects of feeding a grain-free diet with or without methionine, taurine or methyl donor/acceptor supplementation on plasma and whole blood amino acid concentrations in dogs.” Journal of Animal Science vol. 98,Suppl 4 62. 30 Nov. 2020, doi:10.1093/jas/skaa278.112,

Banton, Sydney et al. “Addition of a combination of creatine, carnitine, and choline to a commercial diet increases postprandial plasma creatine and creatinine concentrations in adult dogs.” Frontiers in Veterinary Science vol. 9 1063169. 25 Nov. 2022, doi:10.3389/fvets.2022.1063169,

Banton, Sydney et al. “Addition of dietary methionine but not dietary taurine or methyl donors/receivers to a grain-free diet increases postprandial homocysteine concentrations in adult dogs.” Journal of Animal Science vol. 99,9 (2021): skab223, doi:10.1093/jas/skab223,

Beloshapka, Alison N et al. “Longitudinal changes in blood metabolites, amino acid profile, and oxidative stress markers in American Foxhounds fed a nutrient-fortified diet.” Journal of Animal Science vol. 96,3 (2018): 930-940, doi:10.1093/jas/skx070,  

Dobenecker, B, and U Braun. “Creatine and creatinine contents in different diet types for dogs – effects of source and processing.” Journal of Animal Physiology and Animal Nutrition vol. 99,6 (2015): 1017-24, doi:10.1111/jpn.12383.

Lee, Chang-Min et al. “Correlation between serum homocysteine concentration and severity of mitral valve disease in dogs.” American Journal of Veterinary Research vol. 78,4 (2017): 440-446, doi:10.2460/ajvr.78.4.440,

“Table: 2006 NRC Nutrient Requirements for Adult Dogs (Maintenance).” Merck Veterinary Manual,

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