By Dr. Becker
This article is actually inspired by Ashley, my wonderful veterinary technician who also works at the local emergency animal clinic. Ashley recommended pumpkin and ground turkey to a client at the ER hospital whose pet required a bland diet for diarrhea. These are the foods we recommend at my practice, but in response to her suggestion, Ashley's ER clinic supervisor gave her the following note. It describes the clinic's official recommendation for patients with diarrhea, plus a hand-written explanation as to why Ashley should no longer recommend the bland diet she learned from me:
The subject of fiber is certainly confusing, even for professionals like the veterinarian who drafted these suggestions, but a basic knowledge of the different types of fiber is important in understanding what effect each type will have on an animal's body.
Most medical doctors and veterinarians agree that a healthy diet consists of fresh foods that are rich in antioxidants, phytonutrients, and fiber. But the amount and type of fiber a particular species needs has been more difficult for the medical community to agree on.
Fiber (the tiny threadlike structures in fruits, vegetables, and grains) has historically been defined as the remnants of plant cells that are resistant to digestion, which includes lignans, cellulose, and the indigestible carbohydrates found in plants.1 However, by definition this would omit indigestible carbs found in animal sources, such as chitin, as well as fructooligosaccharides (FOS) and other digestible carbs that are resistant to an animal's digestive enzymes.
For this reason, in 2001 the Institute of Medicine developed definitions of fiber that distinguished between fiber that naturally occurs in foods ("dietary fiber") and other isolated fibers that may be added to foods or dietary supplements (called "functional fiber"). Some examples of specific types of dietary fiber found in plants are cellulose, hemicellulose, lignins, beta-glucans, and resistant starches (found in bananas and legumes). Examples of functional fiber are inulin, oligofructose, plant gums, and pectins.
Fiber can also be classified as viscous and nonviscous, based on its consistency when mixed with water. If the fiber gels in water, as pectins, beta-glucans, psyllium, and some gums do, it's considered viscous. Viscous fiber slows gastric emptying time, can delay the absorption of some nutrients (including sugars) in the small intestine, and lowers cholesterol.2, 3
Soluble and Insoluble Fiber
Fiber is further classified as soluble and insoluble. Soluble fiber, such as beta-glucans, gums, most pectins, and psyllium, disperses easily when stirred into water. Cellulose and lignins do not disperse in water, so they're classified as insoluble fiber.
Research shows that a fiber's solubility does not predict its effect on the body, as previously thought. Soluble fibers bind with fatty acids and slow digestion, which can have a stabilizing effect on an animal's blood sugar levels. Soluble fiber has also been proven to help lower cholesterol in humans.4, 5
Both insoluble and soluble fibers can be fermentable, and most whole plant fibers contain both soluble and insoluble fiber.
Insoluble fiber provides roughage, which helps to bulk up the stool and move waste products through the intestine. Because of this, insoluble fiber prevents constipation and keeps pets regular. In my experience, almost all pet owners and many vets (including the one who chastised Ashley for recommending pumpkin for diarrhea) lump all fiber into this category, assuming all fiber creates the same laxative effect in the gut.
However, some fiber, such as the pectins found in bananas, is actually binding and potentially constipating to mammals. Banana pectins draw water out of the feces, putting it back into the body. When water leaves the colon, harder stools are the result. But in the case of diarrhea, adding a small amount of mashed banana to your dog's bland diet (if he'll eat it) can often actually help reduce the incidence of loose stools.
Fermentable and Nonfermentable Fiber
In addition to solubility and viscosity, fiber can also be classified as fermentable, partially fermentable, and nonfermentable. Fermentable fiber sources, such as pectins, beta-glucans, guar gum, inulin, and oligofructose, provide a food source for the billions of bacteria naturally found in your pet's GI tract. Some fiber sources, such as cellulose and lignin, are nonfermentable. In general, fruit and vegetable fibers are fermentable and grain fibers are nonfermentable.
Current fiber research is focused on the actions and influence of certain types of fermentable fiber in feeding beneficial bacteria in the GI tract. The GI tract is the largest immune organ in the body. GI lymph tissue, called Peyer's patches, as well as Gut Associated Lymphoid Tissue (GALT) is impacted by the balance and health of the microbial microenvironment. Scientists are evaluating how foods can help heal or harm this critically important bacterial balance within your pet's gut, and fermentable fiber can play a huge role in modulating your pet's GI defenses for the better.
Why I Recommend Pumpkin Over Rice as the Foundation of a Bland Diet
Canned pumpkin (100%) provides about 80 calories and 7 grams of soluble fiber per cup, compared to 1.2 grams of fiber in a cup of cooked white rice. Pumpkin is especially rich in soluble fiber (the type that dissolves in water to form a viscous gel, which also coats and soothes irritated bowels). Soluble fiber delays gastric emptying, slowing down GI transit times (and the number of episodes of diarrhea).
When animals have diarrhea, they can lose important electrolytes, including potassium, which puts them at risk of dehydration. Hypokalemia, or low potassium levels, can result in cramping, fatigue, weakness, and heart rate irregularities. Pumpkin happens to be an excellent source of potassium, with 505 milligrams of naturally occurring potassium per cup. Pumpkin is also safer for diabetic patients. Unlike rice, which is a grain, and will ultimately break down into sugar, pumpkin extracts may actually restore beta cell function – beta cells are the cells that produce insulin in the pancreas.6
Rice is a bland source of fiber, but in my opinion, it isn't the most species-appropriate choice for a recovery diet for carnivores. First, it's an unnecessary food. Dogs and cats don't have a nutritional requirement for grain, so feeding pets a pro-inflammatory food when they're already having GI upset seems counter-intuitive to me. Additionally, the FDA has issued a potential warning about arsenic loads in white rice.7
I have many new client visits that occur when a pet's diarrhea was supposed to clear up with a local vet's recommendations, but didn't. I've had many people tell me that although the stools were slightly improved on a homemade diet of cooked rice and hamburger, the rice would often be passed out whole in the stool, giving rise to the question of how much digestion and absorption of this carbohydrate was actually taking place.
Ground Turkey vs. Ground Beef: The Battle of the Burgers
My reason for recommending turkey is simple: hamburger has more fat, which can worsen GI upset, and boiling ground beef doesn't substantially decrease the fat content.
Boiling the meat for a bland diet is important because it's the cooking technique that removes the most fat. Meat must reach 464°F in order for the fats to melt away from the flesh. Boiling water only reaches a temperature of 212°F, so it may only slightly reduce the overall fat content of the meat. The remaining fat can exacerbate pancreatitis and GI symptoms.
Baking the meat at 470°F may seem like a better idea, but it's impossible to remove the fat during baking. Rinsing boiled or baked meat removes surface fat, but it can't remove the fat that remains in the flesh.
For this reason, I recommend fat-free meat for bland diets. You can easily find fat-free ground turkey or turkey breast in most grocery stores, along with 100% solid packed pumpkin in the baking aisle (make sure it's NOT pumpkin pie filling). Organic canned pumpkin is also becoming more readily available.
Clean Foods Are Best, Plus… Alternative Foods for Allergic Pets
Many people (and I'm one of them) prefer to buy organic and non-GMO foods whenever possible. So if you prefer, you can certainly buy fresh, organic pumpkin, steam or boil it, and can it or freeze it for later. If you also have access to fresh, organic turkey meat, even better.
On occasion clients will say, "My dog doesn't like pumpkin," or "My pet is allergic to turkey." In those cases I recommend using skinless, cooked, mashed sweet potatoes (my preference, but white will do), and cooked chicken breast or cod fish (recognizing that fish contains a higher percentage of naturally occurring fat than poultry).
If your pet's diarrhea doesn't resolve in 48 hours, he grows lethargic, or is acting like he's sick, it's time to visit the vet. If a bland diet resolves the diarrhea, transition your pet back to his regular food 24 hours after his stools have returned to a normal consistency. It's important to remember that this recovery diet isn't balanced, and should not be fed long term.