Cholesterol in Cats: What the Number on Your Cat's Panel Means

Your cat's bloodwork shows an elevated cholesterol value and you're wondering what to make of it. The reassuring news: cats don't get clogged arteries from high cholesterol. The more important news: elevated cholesterol in cats is almost always a downstream signal from another disease — and the primary suspects in cats are different from what drives high cholesterol in dogs.

Normal Cholesterol Range in Cats

Most laboratories report a reference range of 75–220 mg/dL for cats. This is lower and narrower than the dog range. Cats are obligate carnivores whose lipid metabolism differs substantially from dogs and humans — they rely more heavily on fat and protein as energy sources, which shapes their baseline lipid profile.

A non-fasted sample can produce mildly elevated cholesterol. If the elevation is modest and the sample wasn't drawn fasted, repeat the test after a 12-hour fast before pursuing further workup.

What High Cholesterol Means in Cats

Diabetes Mellitus

Diabetes is the most common cause of high cholesterol in cats. Insulin deficiency impairs lipoprotein lipase, the enzyme that clears fat particles from the bloodstream after a meal. The result: lipids accumulate. Diabetic cats often show elevated cholesterol alongside elevated glucose and sometimes elevated triglycerides. If your cat's panel shows both high glucose and high cholesterol, diabetes is the leading explanation.

Hepatic Lipidosis (Fatty Liver Disease)

Hepatic lipidosis is one of the most serious and common liver diseases in cats, and it frequently causes abnormal lipid values. It develops when a cat stops eating — particularly an overweight cat — triggering the mobilization of body fat to the liver faster than the liver can process it. Fat accumulates in liver cells, impairing function. The bloodwork picture includes elevated cholesterol and triglycerides alongside markedly elevated ALT and ALP, hyperbilirubinemia, and often hypokalemia. A recently anorexic cat with jaundice and these lipid findings needs urgent evaluation.

Cholestatic Liver Disease

Any condition that impairs bile flow (cholestasis) — cholangitis, cholangiohepatitis, bile duct obstruction — causes cholesterol to accumulate because bile is the primary route for cholesterol excretion. Cats with cholestatic disease typically show elevated bilirubin, elevated GGT (often more elevated than ALP compared to dogs), and concurrent cholesterol elevation.

Hypothyroidism (Rare in Cats)

Spontaneous hypothyroidism is rare in cats — most feline thyroid disease is hyperthyroidism. However, cats treated with radioiodine or bilateral thyroidectomy for hyperthyroidism can develop iatrogenic hypothyroidism. These cats may show elevated cholesterol, weight gain, and lethargy. If your cat was recently treated for hyperthyroidism and cholesterol is now elevated, low T4 is worth checking.

Nephrotic Syndrome

Protein-losing nephropathy in cats — from glomerulonephritis or amyloidosis — drives the liver to overproduce lipoproteins in response to low albumin. The bloodwork pattern: low albumin, high urine protein:creatinine ratio, and high cholesterol together. This combination points directly to renal protein loss.

What Low Cholesterol Means in Cats

Low cholesterol (hypocholesterolemia) in cats signals reduced hepatic synthesis or intestinal loss:

• • Hepatic insufficiency: Chronic hepatitis, cirrhosis, portosystemic shunt — the liver can't produce enough cholesterol. Expect concurrent low albumin, low BUN, and abnormal bile acids.
• • Protein-losing enteropathy: Severe small intestinal disease causing fat and protein malabsorption drops cholesterol along with albumin and globulin.
• • Hyperthyroidism: Excess T4 accelerates cholesterol catabolism, sometimes producing below-normal values — though hyperthyroid cats more often have normal-to-low cholesterol as a result of rapid metabolism rather than flagrantly low values.

Which Tests Come Next

The follow-up depends on what else is flagged on the panel:

• • Elevated glucose + high cholesterol: Confirm diabetes with fructosamine; start diabetes workup
• • Elevated ALT/ALP/bilirubin + high cholesterol: Abdominal ultrasound; investigate for hepatic lipidosis, cholangiohepatitis, bile duct obstruction
• • Low albumin + elevated urine protein + high cholesterol: Urine protein:creatinine ratio; kidney biopsy consideration for glomerulonephritis
• • Post-hyperthyroidism treatment + high cholesterol: Check T4 for iatrogenic hypothyroidism