By Dr. Becker
Is your kitty companion a chowhound, constantly on the hunt for food, food, and more food? Excessive eating is called polyphagia, and an always-hungry cat may display one or more food-seeking behaviors, including:
Gobbling up meals in one session
Eating so fast he vomits immediately afterwards
Accepting food he once refused to eat
Pestering his human for more food or snacks
Counter-surfing in search of food
Begging or stealing food from any available source
Constant Hunger Is Usually a Symptom of Another Problem
If you're thinking to yourself, "MY fussy feline? Are you kidding?" you're not alone. The majority of people owned by a cat are more likely to worry about their pet's lack of appetite than constant hunger pangs.
That's why if your cat does turn suddenly ravenous, you should make an appointment with your veterinarian. Actually, any change in your pet's normal conduct should be investigated, because when cats get sick, very often the first noticeable sign is a change in behavior.
An excessively hungry kitty may have an underlying disease that's causing an increase in appetite. Feeding her more or simply ignoring her demands won't solve the problem. The sooner you find out or rule out potential causes for her hunger, the better equipped you'll be to provide her the help she needs.
Diseases Known to Cause Excessive Hunger in Cats
1. Hyperthyroidism
In older cats, an overactive thyroid is one of the most common reasons for excessive hunger.
Thyroid hormones are responsible for regulating many metabolic processes in the body. In a hyperthyroid cat, circulating levels of thyroid hormones rise progressively higher, which triggers an increase in the metabolic rate.
The increase in metabolism leads to many changes in a kitty's body, which can include an increase in appetite coupled with weight loss and muscle wasting.
About half of cats with hyperthyroidism have increased hunger, and the change can be quite dramatic. Some kitties can easily handle twice the amount of food they normally eat, while continuing to frequently beg or hunt for more.
The reason for this is because the cat's body is trying to compensate for an elevated metabolic rate by increasing the number of calories consumed.
Some kitties with mild hyperthyroidism maintain a normal level of hunger, while others with a rare form of the disorder called "apathetic hyperthyroidism" actually have a decrease in appetite.
2. Diabetes Mellitus
Another disease of middle-aged and older cats — especially if they're fed a dry diet — is diabetes. Since most dry cat food is loaded with carbohydrates and deficient in high-quality protein, it makes sense that a lifetime of eating kibble causes diabetes in aging cats.
The pancreas produces insulin based on the level of glucose (sugar) in the blood. Insulin allows glucose to enter the cells of the body. When glucose levels are high (which normally occurs after a meal), insulin is released.
When there is not enough insulin being released from the pancreas, or there is an abnormal release of insulin coupled with an inadequate response of the body's cells to the insulin, diabetes mellitus is the result.
Sugar in kitty's bloodstream cannot get into the cells, so he can't get the energy he needs to be healthy and active. He'll feel hungry all the time because he's not getting sufficient energy and nutrition from his food.
In addition, his body will start breaking down fat and protein stores to use as energy. As a result, no matter how much he eats, he loses weight.
3. Exocrine Pancreatic Insufficiency (EPI)
Exocrine pancreatic insufficiency is a condition in which there is a decrease or lack of digestive enzymes produced by the pancreas. In cats with the disorder, proteins, starches and fats from the diet aren't broken down sufficiently to be absorbed through the intestinal wall.
This means nutrients can't get into the bloodstream to supply nourishment to the body's tissues. Much of the food that is eaten remains undigested in the gastrointestinal tract and ultimately leaves the body in feces. This causes constant feelings of hunger in approximately half of cats with the disorder.
Left untreated, a cat with EPI can literally starve to death despite how much food is consumed.
4. Inflammatory Bowel Disease (IBD)
IBD is a condition in which the intestines are inflamed, meaning there are high numbers of inflammatory cells present in the lining of the digestive tract. This inflammation causes structural changes in the mucosal lining, which results in dysfunctional digestion and interferes with the body's ability to break down and absorb nutrients from food.
Common symptoms of inflammatory bowel disease include vomiting, diarrhea, and weight loss. Some cats with the disorder have an increased appetite because their bodies can't absorb adequate nutrients from food, which leaves them constantly hungry.
5. Acromegaly
Feline acromegaly, also called hypersomatotropism, is an endocrine-related disease in cats that results from chronic overproduction of growth hormone caused by a slow-growing tumor of the pituitary gland.
Growth hormone stimulates the production of insulin-like growth factors in several organ systems. Kitties with acromegaly often have large bodies, broad faces, enlarged feet, protruding lower jaws, increased spacing between teeth, and a poor coat.
Acromegaly is most often seen in neutered male cats over the age of 8, in particular, kitties with poorly controlled diabetes. Symptoms of diabetes are often the first signs of acromegaly and include excessive thirst, excessive urination, and increased appetite.
Additional Potential Causes of a Cat's Increased Appetite
Cushing's disease (hyperadrenocorticism)
Cancerous or benign tumors that produce insulin, inhibit absorption of nutrients, or cause excess production of growth hormone
Infections that interfere with nutrient absorption
Internal parasites, including tapeworms, roundworms, and hookworms
Lymphocytic cholangitis, which is a disease of the liver
Trauma, tumor, or infection involving the brain's satiety center
Certain medications, including glucocorticoids, benzodiazepines, and antihistamines
When to Call the Veterinarian
If a fussy kitty, or even a cat with a predictably normal appetite suddenly becomes food-obsessed, I recommend a visit to your holistic or integrative veterinarian as soon as possible. Additional watch-outs in an insatiable cat include diarrhea, persistent vomiting, excessive thirst and urination, weight loss, eliminating outside the litterbox, increased vocalization, and hyperactivity.