I recently started feeding my cat Open Farm dry food (he will eat only dry food at the moment), based upon the excellent review on All About Cats. However, now I have read (see link below) that one of the ingredients, dicalcium phosphate, can, with long-term ingestion, cause calcification of soft tissue and kidney stones. Is this a real cause for concern?
Hi there. I contacted Open Farm about this, and they sent back a reply from a couple of their veterinarians. From the vets:
"This sounds like it is taken out of the context of the inclusion levels in a food. Dicalcium phosphate supplies calcium and phosphorus, 2 essential minerals, to the food. Extremely high levels of calcium in the blood can lead to calcification of tissues and renal disease, this is seen with vitamin D toxicity because of the mechanisms within the body. Added at an appropriate level to make sure the calcium and phosphorus meet the AAFCO minimum required nutrient levels without exceeding the maximum levels is not going to lead to health issues in an otherwise healthy pet.
If you google pretty much any mineral ingredient that is used in pet food, you will find warnings because the information is not specific to proper inclusion levels."
And another, who is in agreement:
"I will echo Melissa's (the response I listed above) message. Dicalcium phosphate is a safe source of calcium and phosphorus when included in a formula at appropriate levels. The formation of kidney stones is a bit more complicated than ingesting the recommended amount of calcium and phosphorus in a long term setting. I did a quick literature search to see if I could even find an article they have misinterpreted but could not find one.
As far as calcifying soft tissue is concerned, there would have to be another disease process in the face of a dog or cat eating recommended amounts of calcium, phosphorus and vitamin D."
Hope this helps!
It does. Thank you!
Mitch