Prevention of constipation addresses the retention of water in the poop one way or another. This theme has been discussed several times and we come back to it again. Water makes the difference between a hard stool and a soft stool. Prevention of constipation means to ensure water retention in the stool, using appropriate methods which benefit the cat in various ways.
The unique sensitivity of cats as a species means any plan, whether short or long term, must be especially safe. Each new research study about cats seems to reveal more about their uniquenesses. Cats are strong. tough little creatures and yet they are very sensitive to diet, medications and household chemicals which may be safe for other species.
Treatment for a cat with a chronic condition needs to be ongoing. We want to prevent constipation, not chase it. A cat with chronic tendencies needs a consistent, thoughtful, safe and effective plan to treat and prevent constipation. While the remedies discussed in Acute Treatment can be helpful and some cats may need their ongoing assistance, constipation is not the result of lack of glycerine or stool softeners.
Other healthy cats in the house may have those 'occasional bouts of irregularity' so understanding the digestive tract and constipation prevention can be helpful for them also.
It is not sufficient to see poop in the litter box, we want to support a healthy gut environment.
Diet is the foundation of health, though not the only factor. Genetics plays a role, as does the cat's life style and exposure to environmental influences.
The details of feline nutrition are outside the scope of this website but health, including gut health, cannot be maintained without good nutrition. Cats have unique nutritional requirements, requirements which differ from humans or dogs or other species. However, the components of the cat's diet do not come from another planet, they are the same components of food which are familiar to us all, the same three pillars of diet – protein, fat and carbohydrate – just as they are for other species including our human selves. Cats require different ratios among those three than another species does but those three pillars are still the foundation of a cat's diet. The sources which fulfill those three pillars need to be selected somewhat differently for cats. For instance, cats require that their protein needs be met primarily by animal rather than plant sources, especially to supply adequate taurine, an amino acid which cats do not synthesize well for themselves. But it is protein, not some peculiar and unique need, that is being met.
Some opine that cats are unable to digest carbohydrates. If cats had not evolved with the ability to digest carbohydrates, the feline pancreas would not produce enzymes to digest carbohydrates and the feline pancreas does produce those enzymes. Cats do not produce salivary amylase but they do produce pancreatic amylase. Whole natural foods, including a mouse, are a mix of protein, fat and carbohydrate. The word 'carbohydrate' is a technical term in nutritional language; it is not synonymous with 'veggies' or 'grains'.
The question is not whether cats can digest carbohydrates, they can. The question is, what are appropriate carbohydrate sources for cats and what ratio is appropriate in their diet. We often read that cats do not require carbohydrates, which is true from one angle, cats themselves can manage without carbohydrate content in the diet. But not requiring does not mean cats are unable to digest carbohydrates.
Because cats utilize protein and fat so well to run and support their bodies and maintain their blood sugar levels, little to nothing is left over for the gut bacteria when the diet consists solely of protein and fat. The cat's native diet of mouse and other small prey was not just protein and fat; a mouse offers about three percent carbohydrate and the mouse digestive tract contains some plant material. Something needs to be included in the diet for the cat's gut bacteria, some form or part of plant material. The chapter Gut Bacteria and Fiber covers the benefits in some depth.
If only protein leftovers are available for gut bacteria to ferment, the more pathogenic bacteria benefit at the expense of the beneficial gut bacteria. Those protein leftovers come from shed gut wall cells and recirculating waste products from protein metabolism as well as any undigested dietary protein.
Keeping the beneficial bacteria populations high means they can convert the nitrogenous (protein) waste products into themselves, into more friendly bacterial bodies made of protein, which prevents the more toxic protein waste products from harming the gut wall. Better the friendly bacteria proliferate than those who are less desirable.
The point of fiber is that it is not digestible by the eater, whether that eater is a cat or a human, and so the undigested fiber remains in the digestive tract and flows on to the gut bacteria waiting in the wings. The parts of the included plant material that are digestible will be digested and utilized by the cat herself and, since cats have low dietary carbohydrate requirements, what to include is more critical for cats than for us omnivorous humans who can safely eat a much wider variety of plant foods in greater quantity.
The common term used for fiber naturally contained in food is dietary fiber. Fiber sources such as psyllium, FOS (fructooligosaccharides), inulin, beet pulp fiber, chicory root extract, etc. are called functional fibers. The dividing line is not all that clear since functional fibers may be extracted or concentrated from foods or may be synthesized.
Fiber is termed a prebiotic because it feeds the probiotics which is another word for gut bacteria. The term 'prebiotic' is usually reserved for functional fiber products. Few of us eat our baked squash or dark green leafy vegetables and then announce we just ate some prebiotics.
Ideally the chosen diet provides adequate and suitable fiber content but some cats may need additional help.
Fiber sources should be appropriate for cats and feed the beneficial gut bacteria without overfeeding them.
Cats, or rather their gut bacteria, do better with low-to-moderately fermentable fiber sources. Commercial cat food companies have access to fiber sources which we may not have. Research has shown that beet fiber and rice bran are good fiber sources for cats; they preferentially feed the beneficial gut bacteria and are not highly fermentable so do not risk bacterial overgrowth. Note that rice bran is a source of phosphorus if limiting phosphorus is necessary for your cat. There are about 11 milligrams of phosphorus in 1/8 teaspoon of rice bran though not all the phosphorus is bioavailable. All foods contain some phosphorus.
Guar gum is a common fiber source in commercial canned cat foods and in one study was more highly fermentable than other choices such as beet fiber and rice bran. Some fiber sources such as cellulose and psyllium starve the beneficial bacteria.
Many of us now read the back label of cat food, to choose cat food more carefully, but the type of fiber listed is still an orphan topic. It should not be, fiber is equally important in the dietary scheme even if it does not feed the cat directly.
Changes to the diet or routine of a cat should be made gradually, to allow the cat to adjust and to permit the digestive tract to adapt. Cats sometimes need a new item or routine to be introduced several times before they accept. A tiny smidge of pumpkin can be added to a meal, the amount on the end of a toothpick or fork tine, not to fool the cat but to introduce gradually. There is no advantage to trying to push the process and good reasons not to rush the process. Nothing given can be retrieved but the amount can be increased tomorrow. Monitor the cat and the litter box during this process. These fiber sources are not systemic medications which means there is no precise dose nor is each cat eating the same diet with exactly the same other fiber sources.
Although I have read no research to confirm this idea, I think rotating these extra fiber sources may be a good plan. We have all heard that old cliche, that variety is the spice of life, and there is no reason to think otherwise for gut bacteria. Before cat food came in a bag or can, a cat ate a varied diet of creatures who ate varied diets which provided a varied diet for the cat's gut bacteria. If one dietary fiber source is introduced to a cat who seems to need extra fiber to prevent constipation and that fiber seems to 'stop working', try rotation.
Probiotics - A term for supplements of beneficial bacteria, probiotic supplements proliferate in the marketplace, for pets and for humans. Every choice advertises itself as the best choice. Research in this field truly is still in its infancy compared to how much there is yet to learn. Unless the cat has been on antibiotics or has some other specific health condition that indicates a need for probiotic supplements, my reasoning suggests that feeding appropriate fiber to the cat's resident gut bacteria makes more sense. After all, they already live there so are native residents, and may be suffering due to lack of feeding. Since half or more of the dry matter weight of the poop is gut bacteria, feeding the cat's own gut bacteria with suitable fiber makes sense from that angle, too. We could think of the gut bacteria as a chicken coop. It does no good to bring in ever more chickens if none of them is being fed. If you think your cat appears to require a probiotic supplement, work with your vet.
Recent research brings up the question as to whether live or killed probiotic supplements are better and safer. Those of us familiar with probiotic supplements have assumed that live bacteria are needed, we want to see so many million live organisms per acre stated on the bottle. While it is too early to know what research will eventually show, it is good to know there is a legitimate question as to the safety of live probiotics and may, surprisingly, show benefits from killed sources to which the gut responds. This suggests an additional reason for feeding the cat's own bacteria thoughtfully before reaching for an unnecessary supplement, and for working with one's vet when a supplement appears necessary.
Muscle needs good potassium blood levels to function properly, to respond to signals and intentions, to maintain oomph.
Nerve sheaths, the outer protective covering of nerves, need good body levels of Vitamin B12 to ensure nerve integrity, so that the nerves inside the sheaths are not vulnerable to exposure and do not 'short out' as it were. The usual form of supplemental B12, added to most commercial cat foods and supplements, is cyanocobalamin which requires conversion in the body to an active form. Cyanocobalamin is actually an artifact of the purification process when synthesizing Vitamin B12. The methylcobalamin form of Vitamin B12 does not require the same conversion and is now more readily available for purchase for cats who require supplemental Vitamin B12.
The entire family of B vitamins called B Complex are important to help maintain gut health and to prevent constipation. Vitamins are not nutrients, they are co-enzymes, that is they assist enzymes to do their jobs. Enzymes are not only involved in digestion, enzymes play a role in all metabolic functions and each enzyme is specific to its task. Without adequate B vitamins such as folic acid and Vitamin B12, enzymatic function suffers. First to suffer are those areas of the body with faster cellular turnover such as the gut wall and the blood components. If gut barrier function is reduced, the body itself is more vulnerable to trouble and the enteric nervous system is at risk of damage.
Of course general nutrition is important which a good diet supplies in a balanced format. Extra vitamins and minerals seem to be added to everything commercial made for the cat, from treats to 'appetizers', and many humans who live with cats think that a cat needs a daily vitamin/mineral supplement in addition to the diet. Unless a cat tests deficient, is not eating well, or has a condition that requires extra supplementation, more is not better than enough and may be harmful. The B vitamins are water soluble and so more 'forgiving' as any extra can more easily be dumped into urine rather than accumulating in the body. Still unnecessary supplementation, above demonstrated or diagnosed need, is to be avoided.
Food itself is very nutritious. Before humans came along to invent supplements, every living being on earth was sustained by food, for millions of years, and despite dire warnings to the contrary, food is still nutritious. A stroll through the USDA National Nutrient Database is surprisingly reassuring, in a general sense, about the nutritional value of food items such as meats or the vegetables listed above for dietary fiber.
I have found that both diet and nutrition make more sense when I think of food as having had a previous life. While that is not always a comfortable mental process, it is nevertheless true that items we come to call food once had lives of their own, whether that was an animal life or a plant life, a chicken or a squash. Chickens and squashes have nutritional requirements of their own which are similar to ours in many ways even though they may use different tactics to meet those needs. Squash fruits do not need skeletons, they need strong cell walls to form a sturdy incubator for their seeds. Take a moment to check out 'squash, winter' at the link above, read the list of nutrients and realize that the squash plant was using potassium and magnesium and calcium and phosphorus and B vitamins and amino acids and lipids for its own nutritional agenda, just as we do for ours and cats do for theirs. Squashes go about their business quietly but they still have personal business which requires nutrition.
The listings at that site for the various food plants focus on nutrients of interest to us, the human eaters, but there is more to plants than what we humans find important for the dinner table. Unlike ourselves and our cats, plants are not able to sock a predator in the nose or run and hide so they developed various ways to protect themselves including thick hides, thorns, and chemical warfare.
If you would like to learn more about the complexity of plant chemistry, check out Dr. Duke's Phytochemical and Ethnobotanical Databases to understand why we need to choose plant sources more carefully for carnivorous cats than for omnivorous humans. We ate a large variety of plant foods and evolved with livers which are capable of detoxifying many more plant chemicals than cats can detoxify. Cats, who ate little plant material directly, depended on the livers of their prey species to do the detoxifying for them, then ate the prey. Either cats never developed the necessary hepatic pathways or lost them along the evolutionary trail. We need to select dietary plant material more carefully for cats.
If a change in diet or the addition of appropriate fiber to the diet is not enough to prevent constipation in a cat prone to constipation, osmotic laxatives can be helpful so they are included in this prevention chapter also. Consult with your vet for the best choice and dose for your cat.
Concerns are often expressed about cats with chronic constipation, such as cats with kidney disease, that use of an osmotic laxative will dehydrate the cat because these products draw water to the bowel or hold it in the stool. If producing a normal stool puts a cat at risk of dehydration, more is wrong than constipation and sometimes what is wrong is the human reasoning. Dehydration is not a recommended treatment for constipation! The amount of water needed to normalize the stool in response to an osmotic laxative is the same amount of water by any other method including diet and dietary fiber. This does not mean that these osmotic laxatives should not be treated with respect, of course they should be used conservatively and appropriately. But producing a normal stool by use of an osmotic laxative should not dehydrate a cat.
Again, all changes for the cat should be made gradually, to allow the cat to adjust and to permit the digestive tract to adapt. The digestive tract is remarkably adaptable, within certain parameters, but it takes time to adapt.
Remember, increasing Miralax or Lactulose increases the amount of water in the bowel/stool. If the stool is too soft, reduce the amount of laxative. Osmotic laxatives are dose-to-effect drugs and, unlike most medications, we can monitor the effects in the litter box.
Here, in summary, are the CliffsNotes for this website:
The Glossary helps to clarify the various terms used in the website and is also a helpful review.
“Cats require purity and simplicity.” – SEM