ARE JOINT SUPPLEMENTS “OK” FOR DOGS AND CATS WITH UROLITHS?
Supplements are often used in dogs and cats to support joint health. However, some ingredients in joint supplements may increase the risk of forming stones. Below is a list of ingredients to look for or avoid if your pet has stones.
1. Collagen is a rich source of hydroxyproline and other nutrients that contribute to calcium oxalate stones. When humans consumed 30 grams of gelatin (which contains about 3 grams of hydroxyproline), urine oxalate excretion increased by 50% and glycolate, another precursor of oxalate, increased 5 times (doi: 10.1038/sj.ki.5001906). Avoid feeding collagen-based (or cartilage-based) supplements to calcium oxalate (CaOx) stone formers.
2. Methysulfonylmethane (MSM) increases the availability of sulfur containing precursors or may spare methionine or cysteine metabolism making these sulfur containing amino acids more available to be excreted. Avoid supplements containing MSM in cystine stone formers.
3. Brewer’s Yeast and green lipped mussels are high in purines. Excessive purine excretion has the potential to increase the risk of urate stones especially in pets with genetic or hepatic deficiencies in purine metabolism. Avoid Brewer’s yeast and mussels in urate or other purine stone formers.
4. Vitamin D and Calcium are essential for bone health. They can also contribute to urinary calcium concentration, but the result may not be what you think. In human epidemiological studies, increased calcium consumption was associated with a decreased incidence of CaOx stones. The theory behind this is that intestinal calcium binds intestinal oxalate reducing the absorption of oxalate. If this is true, it may be prudent to give calcium with meals when oxalate is available, instead of during non-feeding periods.
5. Vitamin C has been implicated in contributing to stone formation because of its non-enzymatic conversion to oxalate. Newer studies incorporating the microbiome indicate that certain bacteria convert Vitamin C has been implicated in contributing to stone formation
because of its non-enzymatic conversion to oxalate. Vitamin C also
contributes to short chain fatty acids which might prevent CaOx. In humans, Vitamin C supplementation increases stone risk in men but not women (DOI: 10.22037/uj.v0i0.4275). [EF1] Studies are needed in dogs and cats since unlike humans, pets can synthesize their own vitamin C.
because of its non-enzymatic conversion to oxalate. Vitamin C also
contributes to short chain fatty acids which might prevent CaOx. In humans, Vitamin C supplementation increases stone risk in men but not women (DOI: 10.22037/uj.v0i0.4275). [EF1] Studies are needed in dogs and cats since unlike humans, pets can synthesize their own vitamin C.
6. Glucosamine and Chondroitin are common ingredients in joint supplements. The good news-these appear to be safe. A study showed that regular consumption of glucosamine decreased the risk of stone disease in people (doi: 10.1097/MD.000000000003725). We assume a similar effect in our pets.