Cat Becomes Thinner and Loses Weight – 9 Causes and Treatments
Your cat is getting thinner? This is a cause for concern at any age and can have several causes.
If you notice weight loss, you should get to the bottom of it. The sooner the problem is treated, the easier the therapy and the better the chances of recovery.
The following guide shows what can be the cause of your cat’s weight loss.
In this article you will learn why cats can lose weight quickly – even if they eat enough food. Diseases, parasites and pain are basic possibilities. However, there are other possibilities as well.
Cat becomes thinner and thinner – Causes
Various reasons may be responsible for the weight loss. These include:
Age
Diabetes
Hormones
Parasites
Hyperthyroidism
bad food and intolerances
stress
temperatures
toothache and problems
Below we explain what each of these is all about.
Age as a cause
In humans it behaves with advancing age like in cats: The appetite decreases. In addition, the musculature is reduced.
Understandably, this causes the weight to drop.
Although these developments are to some extent normal, excessive weight loss in old age is a cause for concern. Here you must counteract on the one hand and on the other hand exclude other causes.
Typical for cat seniors are among other things:
Tartar
Toothache
Tooth loss
Chewing becomes more difficult or causes considerable pain. A change to soft, easily digestible and high quality food makes sense.
Occasionally, old cats do not want to or cannot chew at all. Then you should offer liquid food that can be licked. In addition, you can feed high-calorie pastes to counteract slimming.
Regular examinations at the veterinarian are important for older animals to detect problems early and to have them treated.
Weight loss in cats due to diabetes
With diabetes, cats show the same symptoms as humans. This means:
ravenous appetite
extreme thirst
frequent urination
heavy weight loss
fatigue
weakness
apathy and lethargy
So, even though your cat is eating plenty of food, he is losing weight. Frequent urination is another indication of the disease.
However, real information can only be obtained by an appropriate examination. Treatment is with insulin, which is injected under the skin.
With early diagnosis and reliable therapy, your cat can live well with diabetes.
Hormones as a trigger for weight loss
Intact – that is, unneutered – cats and males can experience significant hormonal surges. In cats, this poses the risk of permanent rubefaction.
Unlike in humans or dogs, ovulation does not occur regularly in cats, but is only triggered when a male cat mates.
So long the animal is hormonally considered in readiness for conception. This is problematic in several respects.
On the one hand, your cat becomes restless, sleeps less, has a higher body temperature and often eats less.
Secondly, it can cause cysts to form on the ovaries.
If you do not breed with your cat or if you plan to let it roam freely, you should have it neutered.
Because it is not only the loss of weight, which makes the permanent rolling dangerous.
Parasites lead to weight loss
If your cat has worms, it is not always immediately obvious. The typical symptoms include weight loss:
Vomiting
Diarrhea
Itching in the anal area
loss of appetite
white pieces in feces
The white pieces are segments of worms. However, these are only noticeable when the infestation is very advanced.
In apartment cats, worms are rather rare, but cannot be completely ruled out. If there is a suspicion of the parasites, you should perform a worming treatment or first give a fecal sample.
Hyperthyroidism as a cause of weight loss in cats
With hyperthyroidism (SDÜ), your cat is constantly extremely hungry and drinks a lot. She seems restless and may even become hyperactive.
Blood pressure, pulse and body temperature are often elevated. Metabolism is running at full speed.
No matter how much your cat eats, it will still visibly lose weight. In addition, the coat may become thin and dull.
Other symptoms include:
Kidney problems
Neglect of grooming
Vomiting and diarrhea
Hair loss
constant need to urinate
weakness
slightly sunken eyes
The main way for you to distinguish between diabetes and SDÜ is by behavior. Cats with diabetes become unusually quiet and appear tired and listless all the time.
With hyperthyroidism, the opposite is true and your house cat hardly seems to sleep or rest.
Nevertheless, a comprehensive diagnosis by a veterinarian is necessary to enable the appropriate treatment.
This is surprisingly simple. Often it is already sufficient to administer tablets and offer special food. In some cases, the treatment can be done by administering an ointment into the ear.
But you have to be very careful, because the hormones contained in the ointment can also be absorbed through the skin.
Poor quality food and intolerances
If your cat eats, possibly shows diarrhea and vomiting or strong itching, but otherwise no symptoms appear, the feeding can be responsible for the weight loss.
Poor quality food or an allergy or intolerance to one of the ingredients may be the cause.
It can also be deficiency symptoms, which can also be expressed in breaking whiskers, loss of fur and skin problems or poorly healing wounds.
An exclusion diet and an appropriate change of feed can help.
Stress as a trigger for underweight
If your cat is stressed and frightened, it does not dare to eat enough food in peace. This can already be problematic.
If your cat only gobbles down a few bites, the risk of subsequent vomiting or sober vomiting increases.
By stress and fear your velvet paw is on the other hand constantly in alarm readiness.
The pulse is high, the blood pressure rises and the body temperature can be increased. For this the organism needs accordingly much energy.
This in turn is not absorbed in sufficient measure, which leads to weight loss.
If your cat is constantly or frequently stressed, you should find the trigger for it.
Does the animal have sufficient retreat possibilities, at which it is not disturbed?
Does it feel threatened by other pets and is always on the run?
Some cats don’t do well in hectic, noisy households with children. Others are already stressed by other cats in the same home.
The only thing that will help here is to provide your sofa lion with enough rest and relaxation. High scratching posts and catwalks allow the cat to escape and “get to safety” when needed.
Special scent plugs for cats can have an additional calming effect.
Also, check your behavior and study cat body language. This will help you to identify the exact triggers for fear or stress.
However, it is important to rule out any health problems first.
Temperatures cause cats to lose weight
Cats often have less appetite in the summer. They need less energy to maintain body temperature.
They also do not need to grow a thick coat to protect themselves from the cold. This can cause the body weight to drop.
However, it should not drop alarmingly. If your cat is slimmer in summer, this is perfectly normal. However, it should not be dry or lean.
If it comes nevertheless to it, visit a veterinary surgeon.
Dental pain and problems as a reason for weight loss
If you’ve ever had a toothache or gingivitis yourself, you know how difficult it can be to eat with it.
This is no different for cats.
Discomfort can exist for a variety of reasons. Among them:
broken or split teeth
Tartar
inflammation of the tongue or gums
abscesses
root infections
loose or missing teeth
FORL
These are often accompanied by the following symptoms:
strong salivation
unpleasant, strong bad breath
difficulty chewing
teeth grinding
bleeding
redness and swelling
Avoidance of touching the head area
Food and water is no longer or hardly taken in
In the case of suppurations, you can also sometimes see yellowish bumps.
A regular check of the teeth and gums should be part of your cat’s care.
If you suspect a problem in the area of the mouth, you should immediately consult a veterinarian. He or she will be able to detect problems that are not visible from the outside through x-rays.
These include the dreaded disease FORL. The acronym stands for Feline Odontoclastic Resorptive Lesion. Teeth and tooth roots dissolve in the process.
A cure is currently not possible. The only possible treatment is the removal of the affected teeth.
What to do if no reason for the weight loss is found?
If none of the above causes is found to be responsible, it is worthwhile to conduct a comprehensive general examination and take a detailed medical history.
On the one hand, it is crucial to consider the cat’s living conditions and diet as well as its breed.
On the other hand, organs should be considered that have not yet been examined.
The following checklist will help you to give your vet useful information if necessary or to ask for further diagnostics.
Free roaming or not?
Outdoor cats can quickly come into contact with pathogens and toxins, ingest foreign bodies, or sustain injuries. Because cats are masterful at hiding pain and illness, problems are often detected late.
Check throat, stomach and intestines
Does your cat have a sore throat, causing difficulty swallowing? Is there a tumor or ulcer in the esophagus? Is there gastritis or a blockage in the intestines?
Check bladder
Bladder infections, urinary calculi and bladder stones can cause considerable pain. They affect the whole organism and can even lead to kidney damage. This can also cause a loss of appetite.
Examine the pancreas
The pancreas produces essential digestive enzymes. If it no longer works properly, for example due to inflammation, the nutrients from the food cannot be absorbed in sufficient quantities. However, the necessary enzymes can be added to the feed. In addition, a change in diet and drug treatment can bring improvement.
When the cat loses weight
If your cat loses more and more weight, you should act early.
If there is already underweight, the organism is already considerably weakened. The treatment and the following reconstruction will take much longer and will be more difficult.
Regular controls and attentive observation by you help to recognize complaints early and to be able to act accordingly.

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