Raw Information and Resources

Feline Nutrition Foundation Archive

Feline Nutrition Home PageBeginner
Feline Nutrition's Easy Homemade Cat Food RecipeBeginner's Luck: Where Do I Start?How to Transition to a Raw Cat Food DietJust What is a Raw Cat Food Diet, Anyway?Easy Raw Cat Food for the Busy PersonYour Cat's Nutritional Needs: The BasicsThe Benefits of Raw Food for CatsThere's No Such Thing as a Vegan CatEight Effective Bribes for the Kibble AddictDon't Let Your Senior Cat Become a Skinny Old KittyThe Skinny on Senior Cats: Metabolism ExplainedSlimming Your Cat: What Works, What Doesn'tHigh Pressure Processing: The Future of Raw Cat Food?No Bull, Taurine Is a Must for KittyAdding Taurine to a Raw Cat Food DietHomemade Cat Food, a Balancing ActThiamine in Raw Food for CatsCalcium Supplements in Homemade Cat FoodDon't Let Calcium/Phosphorous Ratios Scare YouVitamin E: Liquid vs. PowderArginine: Essential and Abundant for Cat NutritionLysine and Raw Cat Food DietsCare to Compare? Wild vs. Domesticated PreySpooked By Salmonella: Raw Cat Food!Tips for Transitioning Your Finicky Kitties'Natural' vs. 'Grain-Free' Cat FoodFiguring Out the Carbs in Canned Cat FoodTake Heart, But Not Too MuchThe Case Against Cod Liver OilFeeding Kitten Food to an Adult CatRaw Cat Food vs. More FiberProbiotics, Digestive Enzymes and Raw Cat FoodRaw Cat Food and Kibble Don't MixFeline Nutrition: Who Bears the Responsibility?Pet Food and Feeding: Personal RuminationsReading a Pet Food Ingredient Label
Bio-Inappropriate: The Dangers of Dry Cat FoodFeline Diabetes: The Influence of DietFeline Inflammatory Bowel Disease: Nature and TreatmentFeline Hyperthyroidism: What You Need to KnowA Diet for Your Cat's Urinary and Kidney HealthConstipation: Real Help for Your CatPhosphorus Can Be Key for Cat KidneysWater, Water and Water Battles CrystalsFeline Cystitis and Bladder/Kidney StonesHigh Blood Pressure: Yes, Your Cat Can Get It, TooNutrition is Vital When Treating Feline LeukemiaFeline Pancreatitis: Signs of TroubleAnother Furball? It Might Be Feline AsthmaOpen Wide: The Basics of Kitty DentalsCat Scratch Fever: How It Affects CatsDiet and Your Cat's Cancer RiskChunks and Bones For Your Cat's TeethA Cat's Food Allergies and Intolerances ExplainedHow Toxoplasmosis Affects CatsAvoiding Hepatic Lipidosis in Your CatHow Raw Food for Cats Affects Blood Test ResultsGet Kitty Exercising to Trim DownSalmonella: The Chicken or the EggSafe Handling Practices for Raw MeatIf You're Feeling Stressed, So Is Your CatChoosing the Right Insulin for Your Diabetic CatA Veterinarian's View on Raw Cat Food: Andrea Tasi, VMD
Answers: What Exactly is an 'Obligate Carnivore?'Answers: What Dry Food Does to Your Cat's AppetiteAnswers: Why Won't My Cat Eat?Answers: Who Were Pottenger's Cats and Do They Matter?Answers: To Grind or Not to Grind Raw Cat Food?Answers: What Dry Food Does to Your Cat's TeethAnswers: What Dry Food Does to Your Cat's FurAnswers: What Dry Food Does to Your Cat's PeeAnswers: What Dry Food Does to Your Cat's GutAnswers: One More Reason to Ditch Dry Cat FoodAnswers: Do Cats Need Dietary Fiber?Answers: Cats in a Bind over PhosphorusAnswers: Let's Talk About Cat BarfAnswers: Making Raw Cat Food Kitty-SizedAnswers: Raw Food for Cats, What About Eating Bones?Answers: Getting Kitty to Like ChunkyAnswers: Are Exotic Meats Nutritious or a Novelty for Cats?Answers: Raw Food and Outdoor Cats, What About Worms?Answers: Take a Deep Breath and Cut the Mouse in HalfAnswers: The Stomach Contents of PreyAnswers: Flaxseed Oil for Kitty?Answers: Plant vs. Meat – The Protein Feud for Cat FoodAnswers: Kitty That Only Wants FishAnswers: Is It Okay for My Cat to Have Milk?Answers: Feed My Cat a Raw Egg Yolk?Answers: Raw Cat Food for My Cat's Mystery Allergy?Answers: Your Cat's Acid StomachAnswers: Cat Urine Ph, Why It MattersAnswers: Kittens Go Through Teething, TooAnswers: Raw Cat Food for All of Those Kittens!Answers: Why Did My Cat's Fur Get So Silky?Answers: Goaltending the Cat Food BowlAnswers: Who Are AAFCO and the NRC?Answers: Taking the Complexity Out of B Vitamins for CatsAnswers: The Paradox of Prescription Diets for Cats
How to Think Like a CatRaw Meaty Bones for Cats: Adult Supervision Required!Let Me Tell You About Raw Cat Food. Hey Come Back!But Kitty, What Nice Teeth You Have...Sasquatch vs. My CatI Worry About My CatYour Cat Worries About ThisYour Kitty May Need to Go to Chunk SchoolAre Cats Clandestine Consumers?Dry Cat Food – The Big EasyEight Cat CuriositiesCats and Cantaloupe: A Method to their MadnessThe Myth of the Finicky CatFalling Off the Cat Food Recipe CliffCat Daddy Talks Cat DietThe Popularity of Cat PoopThe Most Important Member, YouYou Said You Feed Your Cat, What?Oh! Those Dirty Little Kittens!It's My Cat's House, I Just Live ThereBlack Cats Are Not Unlucky at AllLessons From the Stoic CatIs There a Cat in the House?Rice Isn't NiceDon't Let it Bug You Kitty!Tell Your Cat to Chew on This!Cat Longevity and the Ultimate Test?Bug Patrol and Cat Stampedes: Life with Lots of CatsWhat Scraps?
Feeding Raw Food In Australia: What's Up Down UnderThe Cemetery Cats of Buenos AiresCats Are Paying Attention to Your FeelingsCheetahs in Captivity Need a Better DietIt Started With a Caracas Cat Named CaterpillarConsidering a Hybrid Cat?Tales from the Trenches: Feeding Kittens a Raw DietSaving Alistair: How Lyn Thomson Helped Stop IBD 11,000 Miles AwayRaw Cat Food Essentials and Fun Stuff, Too!There's No Kibble Served at the Big Cat RescueWhat Bob Dole Taught Me About Raw FoodAn Answer For Alex: Raw Food and Tight RegulationMangiare Crudo in Italia (Raw Fed in Italy)Melamine to Frankenprey: A Documented JourneyCould Everything We Know Be Wrong?A Brief History of Commercial Pet FoodWhen a Vegetarian Feeds A Raw DietRead Me! Great Books About CatsDuke's Story: Inflammatory Bowel DiseaseAdoption: What Should We Feed Our New Kitten?Malaysian Kittens Meet Frankenprey!Raw Food Co-ops: Make Buying Less Trying!Feeding Cats Ring Dings and Krispy Kremes
One Page Guides
Cats Are Cats!What Should You Be Feeding Your Cat?The Dangers of Dry FoodRaw Feeding for BeginnersTransitioning to a Raw DietEasy Recipe for Success
About Us
Welcome to Feline NutritionThe Feline Nutrition FoundationA Message from the FounderThe Feline Nutrition Foundation Mission StatementThe Feline Nutrition Team

Blog & Newsletter

Current Specials

Current Specials

This content is archived from the Feline Nutrition Foundation

Probiotics, Digestive Enzymes and Raw Cat Food

Updated: Thursday, May 23, 2019 06:05 PM
Published: Saturday, October 09, 2010 01:49 PM
Written by Fern Crist, DVM

I've heard it is recommended to add probiotics and digestive enzymes to cat food, especially when first transitioning from dry to raw food. Should I add these to the food when I mix up a batch or add them only when feeding each meal? I don't know if these two products are sensitive to storage and freezing.

I cannot answer this question without first addressing a deeper one: whether the addition of probiotics and digestive enzymes will actually aid in the transition to a new food. I find this recommendation on numerous websites, but what I don't find is any scientific support for it, or against it.

So, no scientific basis for a decision. Now what?

It is important that we understand that the absence of scientific support for a theory does not disprove the theory. It often means simply that the science has not yet been done. Some scientific minds think in terms of: "If it isn't proven, it must not be so." Such closed-minded hubris is a roadblock to true progress. I like this better: "If it isn't proven, but we see substantial anecdotal support for it, it might be so. This should be studied." The nature of science is continual change in what we perceive as truth.

The use of probiotics and digestive enzymes in food, not just for transitional purposes but all of the time, is strongly advocated by many. Probiotics are said to boost the immune system.¹ There is also some evidence that certain probiotics can alleviate diarrhea, at least in humans.² Digestive enzymes are, not surprisingly, assumed to aid in digestion. But this is not as simple as it may seem. Let's examine the idea.

Enzymes of many sorts are present in raw tissues, but are denatured by cooking. These enzymes in raw foods are said to be beneficial. Evidence to support this is almost completely anecdotal. Yet the volume of anecdotal evidence would force the strongest skeptic to at least examine the idea.

Here's the logical problem with the enzyme theory: there's more than one way to denature an enzyme. Enzymes, being proteins, are denatured by strong acids, and there are not many acids stronger than what is in stomach of an obligate carnivore. Ingested enzymes are denatured in the stomach, so they aren't making it to the small intestine and hence cannot be helping with actual digestion. Many veterinary discussions of this subject stop right there. Enzymes are not getting past the stomach, so the whole idea must be faulty.

This conclusion is poorly reasoned. If cats fed food with active enzymes are healthier, and the mass of anecdotal evidence supports this, then possibly the enzymes are acting not as an aid to digestion, but in some other way which we don't yet understand.

The flip side is that these enzymes appear to be safe.³ So why not add them? It is reasonable to use them based upon what we know anecdotally. Will they help with the transition process? That is unknown.

Now back to your original question. Will they survive the freezing process?

The probiotic, being an active culture, will likely not. However, the base of many probiotics is animal digest, which is a flavor enhancer, and that will survive freezing. But, flavor enhancers work better when warm. So I would not mix the probiotics into the food prior to freezing, but add it at room temperature just before feeding.

Digestive enzymes will freeze just fine. No worries there. However, you are choosing raw cat food at least in part because it already has enzymes that cooked food does not. Will the addition of more give any benefit? Again, that is unknown. The only advice I can give on this question is that some enzyme preparations taste bad to cats and some don't. If you are going to do this, be sure you choose a preparation that won't turn your cat off the new food.

I hope my soapbox today will send some graduate student off to examine scientifically whether, and exactly how, enzymes in food provide health benefits.

And I hope that your cat will transition easily to a much more natural and healthy food!

Note: Feline Nutrition provides feline health and nutrition information as a public service. Diagnosis and treatment of specific conditions should always be in consultation with your own veterinarian. Feline Nutrition disclaims all warranties and liability related to the veterinary advice and information provided on this site.

Fern Crist, DVM is a graduate of the University of Georgia and has a feline-only practice in Fairfax, Virginia.

1. G. Solano Aguilar, T. Ledbetter, H.D. Dawson, K. Andrews, R.B. Harvey, N. Schoene and J.F. Urban, Jr, "The Effect of Probiotic Bacteria on the Immune System of Weaned Pigs Monitored by Real Time PCR," Proceedings of the 18th International Pig Veterinary Society Meeting, Hamburg, Germany, October 2004, 380.

A.R. Lomax and P.C. Calder, "Probiotics, Immune Function, Infection and Inflammation: A Review of the Evidence from Studies Conducted in Humans," Current Pharmaceutical Design 15, no. 13, 2009, 1428-1518.

2. Michael de Vrese and Philippe R. Marteau, "Probiotics and Prebiotics: Effects on Diarrhea," Journal of Nutrition, no. 137, March 2007, 803S-811S.

E.S. Huebner and C.M .Surawicz, "Probiotics in the Prevention and Treatment of Gastrointestinal Infections," Gastroenterology Clinics of North America 35, no. 2, June 2006, 355-365.

3. Consult with your veterinarian before adding probiotics or digestive enzymes to your cat's diet. It may not be advisable to add these supplements if your cat is immunosuppressed or diabetic.

4. Please see "How to Transition Your Cat to a Raw Diet."