Three nutritional deficiencies are most commonly linked to pica in cats: iron, vitamin B12, and fiber. When a cat’s body lacks these nutrients, it may start eating non-food items like fabric, plastic, cat litter, or cardboard. That said, pica isn’t always driven by a deficiency. Stress, boredom, genetics, and underlying medical conditions can all play a role, so identifying the actual cause matters before jumping to solutions.
Iron Deficiency and Anemia
Iron deficiency is the most well-documented nutritional trigger for pica in cats. When iron levels drop low enough to cause anemia, cats may begin eating or licking non-food materials such as litter, concrete, or dirt. The behavior appears to be the body’s attempt to compensate for what it’s missing, though the exact mechanism isn’t fully understood.
Iron-deficiency anemia in cats usually isn’t caused by a poor diet alone. More often, it results from chronic blood loss due to intestinal parasites (especially hookworms or fleas in heavy infestations), gastrointestinal bleeding, or conditions that interfere with iron absorption. If your cat has suddenly started eating strange things and also seems lethargic, has pale gums, or is losing weight, anemia is worth investigating. A basic blood panel can reveal whether red blood cell counts and iron levels are low.
Vitamin B12 Deficiency
Low vitamin B12 is another recognized driver of pica behavior. Cats can’t produce B12 on their own, so they rely entirely on their diet. Most commercial cat foods contain adequate levels, but absorption is the more common problem. Cats with inflammatory bowel disease, chronic pancreatitis, or intestinal lymphoma often struggle to absorb B12 from their food, even when intake is sufficient.
B12 deficiency tends to develop gradually, which means pica may appear alongside other subtle signs like decreased appetite, weight loss, or changes in energy level. Your vet can check B12 levels with a blood test, and if they’re low, supplementation through injections or high-dose oral supplements typically resolves the deficiency faster than dietary changes alone.
Low Dietary Fiber
Fiber occupies an unusual place in feline nutrition. It’s not classified as an essential nutrient, and pet food guidelines don’t set a minimum requirement for it. Yet veterinary sources consistently list low fiber as a factor in pica. The theory is that cats on very low-fiber diets may not feel full after eating, which drives them to chew and ingest non-food materials to satisfy that physical sensation of fullness.
This is especially relevant for cats fed all-meat or very high-protein diets that contain almost no plant matter. In the wild, cats consume small amounts of fiber from the stomach contents of prey, fur, and connective tissue. A domestic diet that eliminates fiber entirely may leave a gap that some cats try to fill on their own. If your vet suspects low fiber is contributing to pica, they may recommend switching to a higher-fiber food or feeding smaller meals more frequently throughout the day to improve satiety.
How Vets Identify the Cause
Because pica has so many possible triggers, vets typically don’t assume a deficiency is the cause without evidence. A standard workup includes blood tests, urinalysis, and fecal testing. Blood panels can reveal anemia, low B12, and signs of organ dysfunction. Fecal tests check for intestinal parasites that could be causing chronic blood loss and nutrient malabsorption. If those results come back normal, the focus shifts to behavioral and environmental causes.
It’s worth noting that many cats with pica have perfectly normal bloodwork. Deficiencies explain some cases, but not most. A cat that chews on plastic bags or eats houseplants may be doing so out of boredom, anxiety, or compulsive behavior rather than a nutritional gap.
Breed and Genetic Factors
Some cats are simply more prone to pica regardless of their diet. Oriental breeds, particularly Siamese and Burmese cats, show a higher incidence of wool-sucking and fabric-eating behavior, which suggests a genetic component. This type of pica often starts in kittenhood and may persist throughout life even when nutrition is optimized.
For these cats, pica functions more like a compulsive behavior than a symptom of deficiency. Environmental enrichment, puzzle feeders, increased playtime, and in some cases behavioral medication are the primary management strategies. Ruling out nutritional causes is still important, but if your Siamese has been chewing blankets since she was a kitten, genetics are the more likely explanation.
Dietary Changes That Help
If a deficiency is confirmed, correcting it usually reduces or eliminates pica behavior over a few weeks. For iron-deficiency anemia, treating the underlying cause of blood loss is the priority. For B12, supplementation works quickly. For fiber, switching to a food with higher fiber content or adding a fiber supplement can make a noticeable difference.
Even when no clear deficiency exists, some dietary adjustments are worth trying. Feeding smaller, more frequent meals can reduce the urge to eat non-food items. Offering safe alternatives like cat grass gives cats an outlet for chewing behavior. And ensuring the food meets established nutritional guidelines (look for an AAFCO or FEDIAF completeness statement on the label) helps rule out the possibility that the diet itself is the problem.
Cats that eat non-food items are at real risk of intestinal blockages, which can be life-threatening and require emergency surgery. Even if the pica seems harmless, removing access to dangerous materials (string, rubber bands, plastic, fabric) while you work on identifying the cause is the most important immediate step you can take.