What are the common causes of obesity in dogs and cats?

Common causes include calorie intake exceeding expenditure, lack of exercise, and changes related to age and lifestyle. In some cases, endocrine or metabolic conditions need to be ruled out — your vet can advise on appropriate tests.

How can I help my pet lose weight safely?

The main approach is an individualised diet and gradual exercise plan developed by your vet or a veterinary nutritionist. Avoid drastically reducing food or introducing intense exercise on your own. Regular weigh-in check-ups are important to track progress.

How long does it take to see results during a weight loss programme?

Healthy weight loss typically targets a slow, steady decrease each week or month. Results vary by individual and programme, and it often takes several months to see noticeable improvement — adjust as directed by your vet.

What information should I prepare before the appointment?

It helps to bring a recent weight log, a daily food and feeding time record, short activity videos, and any recent blood or imaging test results — this allows your vet to assess the situation quickly and give tailored advice.

How much do the tests and treatment usually cost?

Costs vary by clinic and region — ask your vet for an estimate before proceeding.

Disease Guide

Pet Obesity in Dogs & Cats: Symptoms, Diagnosis & Weight Management [2025]

Obesity is a common problem in pets, increasing the risk of diabetes, arthritis, and heart disease — managed through dietary changes and exercise.

Take 1 minute to check the symptoms first

Last updated: 2026/01/06

Pethealthmap Editorial Team

Sources: WSAVA, AAHA, Veterinary Internal Medicine Society

When to See a Vet

Seek immediate veterinary care (emergency)

•Rapid breathing, open-mouth panting, or inability to settle
•Sudden loss of consciousness or persistent weakness and collapse
•Persistent vomiting with inability to eat or drink

Schedule a veterinary appointment as soon as possible (within 24-72 hours)

•Significant rapid weight gain over a short period
•Marked decrease in activity, reluctance to exercise or jump
•Changes in elimination habits or persistent abnormal constipation

01What Symptoms Indicate a Problem?

Overweight dogs and cats often present with reduced activity and changes in body shape — owners can detect these through daily behaviour and physical appearance.

Reduced energy and vitality — tiring more easily or sleeping more than usual
Changes in appetite (increased or decreased), yet weight continues to rise
Reluctance to walk, jump, or engage in play — noticeably lower activity levels
Changes in toileting habits, such as constipation or altered frequency
Rounded body shape with visible fat accumulation around the abdomen, waist, and back
If you suspect obesity or notice rapid changes, schedule a weight assessment with your vet soon

02What Should You Watch for at Home? Key Observations and When to Seek Emergency Care

Keeping track of a few key points at home helps your vet understand the progression and put together a weight loss plan faster.

Weigh your pet at the same time each day and record the trend
Keep a detailed log of food types, amounts, and feeding times each day
Estimate and record daily water intake — note any significant changes
Record the frequency, consistency, and colour of stools
Film short videos of your pet's activity (walking, playing, going up and down stairs)
Note when you first noticed the weight change or behavioural shift and bring this to the appointment

03How Will the Vet Diagnose This? Common Tests

Your vet will use a physical exam and necessary tests to identify the cause of obesity and any complications, then assess the most suitable treatment approach.

Physical examination

assessing body condition, fat distribution, muscle mass, and mobility

Blood tests

evaluating liver and kidney function, blood glucose, and possible hormonal markers

X-rays

assessing organ size, joint load, and skeletal stress

Abdominal ultrasound

checking organ condition and abdominal fat accumulation

Advanced imaging (CT/MRI)

used when organ complications or complex conditions are suspected

Referral to a specialist clinic with endocrine and imaging capabilities is recommended for further evaluation

04What Treatment and Care Is Needed After Diagnosis? Medications, Diet Adjustments & Care Guide

Treatment centres on individualised dietary control, increased activity, and long-term monitoring to maintain a healthy weight.

Follow an individualised weight-loss diet plan developed by your vet or a veterinary nutritionist
Schedule regular weigh-in appointments and adjust the diet and goals based on results
If needed, have a specialist assess whether further tests or adjunct interventions are required
Gradually increase safe daily activity at home and keep a log of exercise duration and type
Continue monitoring weight and lifestyle habits, and schedule regular comprehensive health checks
A veterinary team able to provide nutrition and behaviour counselling is recommended for ongoing follow-up

05What Should You Prepare Before the Vet Visit? Key Information to Help Your Vet Assess Quickly

Bring a weight log from the past month showing the trend

List the types of food, portion sizes, and feeding times for a typical day

Record changes in water intake, toileting habits, and energy or activity levels

Bring any recent blood or imaging test results if available

Prepare short videos of activity or eating behaviour, noting when each was filmed

Bring a list of all current medications and supplements

Book an appointment at a clinic or specialist hospital that can run blood tests and a nutritional assessment

This content is for reference only and cannot replace a professional veterinary diagnosis. If your pet shows signs of illness, please seek veterinary care promptly.

Related Symptoms (You May Also Be Looking For)

Lethargy

Decreased activity

Anorexia

Loss of appetite

Weight Gain

Increased body weight