Updated 4/27/24

Every now and then, I go through a kind of “Litter Dance,” in which I try out a variety of kitty litters on my gang of four. Fortunately they’re amenable to the changes, which allows for a thorough evaluation of the different types of litter. I thought I’d share some of my most recent experimental results, as well as research into types of litter that I haven’t tried.

Miscellaneous (but Important) Litter Facts:

  • Cats prefer the softest texture they can find, so if your cat is going outside the litterbox (and your veterinarian has ruled out a medical issue), try a clumping litter. (Click here for more info on litterbox avoidance.)
  • Pelleted litters do not clump.
  • If litter tracking is a problem, this is a great litter mat that really pulls the stuff out from between their toes. It has two layers that allows litter to fall through to a compartment that can easily be emptied. It also stands up to a vacuum.
  • All cats will ingest a small amount of any type of litter while grooming (except pearls). Normally it will pass through without any problems, but in cats with dietary sensitivities, plant-based litters could become allergenic.
  • Some cats may prefer a gradual transition from one litter to another.
  • Even if the litter says it’s flushable–don’t. Flushing cat litter is illegal in California; it’s thought to be a source of Toxoplasma, a parasite implicated in the death of sea otters. It isn’t okay anywhere else, either…although plumbers will love you for it as you run up their bills!
  • Even if the litter says it’s compostable, don’t. It could potentially transmit parasites or diseases to wildlife. Certainly don’t use it around plants being grown for food.
  • Don’t use scented litter. Poop is never going to smell pretty, no matter what! Heavy fragrances can repel your cat and could even irritate her respiratory system.

Litter Choices

Clay: It’s the most common, and certainly the cheapest. Whether standard or clumping, clay litter is made of clay, which may also contain silica and other minerals. Most clay litters contain bentonite clay, also called sodium bentonite, montmorillonite or montmorillonite clay (the names are used interchangeably, even within the industry). However, clay has several serious problems:/div>

  1. It’s dusty. Even “dustless” litters still give off very fine particles that can penetrate deep into the lungs. Clay litter may contain silica, which can damage lung tissue, resulting in fluid accumulation and scarring (“silicosis”).
  2. There has been only one published case of possible clay toxicityin a cat who was known to eat clay litter. It’s a sad story of stupid owners, and the cat was killed because of their abysmal moronicity and colossal stupidity; but it does illustrate the potential toxicity of clay’s components.
  3. Many people have reported illness, intestinal blockages, and even death in kittens and cats who ingested clay litter.
  4. Clay is strip-mined in an environmentally unfriendly manner.
  5. Clay is a finite, non-renewable resource.
  6. Clay is radioactive. Reporter Daniel Engberg, writing for Slate.com, did the research, and found that, “Yes, the clay in cat litter does give off radiation in very small quantities. There is naturally occurring radiation all around us; the radiation in cat litter comes from trace amounts of uranium, thorium, and potassium-40.” Even if the amounts are small, your cat is exposed to it many times a day, every day, for life. Radiation damage from any source is cumulative; so it is theoretically possible that cancer or other radiation-related illnesses could occur from this exposure.

Certainly clay should never be used for young kittens, who are apt to sit or fall in it, or walk through wet spots, and thereby ingest a larger amount when cleaning themselves; the same goes for cats with a lot of fur between their toes that can pick up a larger quantity of litter.

However, I must give credit to “Dr. Elsey’s Cat-Attract” litter, which has saved a lot of cats with litterbox-avoidance issues from relinquishment or euthanasia. The texture is finer than regular clay but coarser than most clumping litters, and it suffers from the same issues as other clay products. But if it’s the only litter your cat will use, then use it–at least until your cat is reliably re-trained. Then you can gradually switch to something more cat- and environment-friendly.

Newspaper: Some of us remember the primitive days before kitty litter, when we spent many hours tearing newspaper into narrow strips and shreds; and to our cats’ everlasting credit, they used it! Today, newspaper is compressed into  pellets that disintegrate when wet. A lot of folks swear by it, but I can’t imagine how stepping on hard little pellets can be comfortable for a cat, let alone declawed cats for whom it is sometimes recommended. Its odor-neutralizing ability is limited. There is also a concern with potential toxicity from the chlorine used to bleach the paper, as well as the ink. While older petroleum-based inks were quite toxic, many of today’s inks are safer (although they are made from genetically modified soy, which is itself problematic). However, colored inks are still petroleum-based. The amounts of soy and chemicals absorbed or ingested may be small, but again, long-term chronic risks are unknown. Purina’s Yesterday’s News is the most prominent brand; Petco also makes its own line.

Corn: Clumping litter made from corn has become quite popular, despite its higher cost. It’s made by grinding corn cobs into dust and then gluing it into bigger grains. It’s less dusty than clay (though it does eventually degenerate, especially with vigorous scooping). However, the dust seems to be much less irritating than clay. (Personally, my own asthma improved about 90% with the corn litter!) The clumps are not quite as adherent as clay, so you have to gather up the little pieces that fall off; but my cats like it and use it perfectly. It also tracked less than the clumping clay we used previously.  It does a reasonable job of odor control.  World’s Best is the most popular corn-based litter, and the company gets extra kudos for its donations of thousands of pounds of litter to shelters. Of course, more competitors are now making similar products. Corn is a renewable resource, but most U.S. corn is genetically modified. The small amount of dust a cat would naturally ingest through grooming is not a significant concern; but don’t use it if your cat is one of the few who likes to eat it. Theoretically, it could also pose an allergen risk to sensitive cats, though I have not heard of any cases of this happening. NOTE: Although starter chicken feed looks and acts exactly like corn-based kitty litter (and comes at a much lower price), chick feed contains vitamins, minerals, and sometimes even antibiotics. I have seen serious toxicity from using chick feed in this manner.

Wheat: The idea behind wheat litter is similar to corn, and its properties are also similar. No U.S. wheat is genetically modified, so that is a small advantage; but breathing the dust or ingesting the litter may be a problem for gluten-intolerant cats. The primary brand is Swheat Scoop, a company I take issue with because it promotes its products for “newly declawed cats.” Maybe I’m too sensitive about the issue, but giving people another excuse for declawing their cats just does not sit well with me. I see no advantages to Swheat Scoop that aren’t available in other products. I also disliked its intensely perfume-y odor, though I see they now make a “lightly scented” version.

Walnut Shells: This newcomer is similar in texture to corn and wheat litters. It’s a sustainable and renewable resource, and makes use of material that is otherwise a waste product. The only contender in this category so far is Blue Naturally Fresh. This litter has no odor itself, and is pretty good at odor control. The clumps adhere a little better than corn and wheat. Despite the dustless claim, it does produce a dark dust that is more visible due to its brown color. Vigorous scooping and shaking makes more dust; I’ve learned to be a gentle scooper! It does seem sturdier than corn and wheat, which break down more quickly. The walnut litter tracks about the same corn and wheat, but less than clay.

Pine: Pelleted pine sawdust is a favorite with many people, but most cats are repelled by the smell of pine. Many cats find the pellets unpleasant to walk on. Like other pellets, pine disintegrates when wet, which can be both a blessing and a curse. The aromatic oils in raw pine are toxic to cats, so if you want to try it, be sure to get a kiln-dried product (although some oils will still be present). Never use the similar-looking pellets made for wood stoves, which contain 100% of the toxic factors.

Crystals (Pearls): These are made from silica gel. Not all cats will reliably use them (including mine). Pearls are larger than crystals but have the same absorbent properties. Crystals get tracked around the house more than pearls. Reviews are mixed; people like their lighter weight but not the high price. Quality apparently varies widely among brands. Many people complain that it is quite painful to step on stray crystals in bare feet–and this is okay for the cat because…?

Perfect Litter Alert Specialty Cat Litter: This product purports to change color (to pink) if your cat’s has a urinary tract infection or inflammation (FLUTD). It’s made from vermiculite and perlite, which are commonly used in planting mixes. It’s lightweight and, according to one review, works as advertised. However, it is very expensive and may not be practical for everyday use, especially with multiple cats.

Smart Litter: This is made from grass… you can’t get much more renewable than that! It’s a soft, lightweight clumping litter that does a great job at odor control And unlike some other plant-based litters, it retains its clumping ability for a long time… at least a month, in my 2-cat household.

Sustainably Yours: This fine-grained litter is made from corn and cassava. It’s my current favorite because it’s made from renewable resources, it’s relatively light-weight. The very fine version can get tracked around despite a litter mat; but they make one with a coarser grain that may be better (I haven’t tried it.) It’s available at most pet stores.