Obesity in Cats

Key Takeaways

A cat is considered obese when its weight exceeds 20% of its estimated ideal body weight. 

• Obesity most commonly occurs as a result of consuming too many calories relative to the amount burned

• Obesity is the most common nutritional disorder in cats, especially as they age

• Obesity is associated with decreased life expectancy and is correlated with other diseases like diabetes mellitus, osteoarthritis, liver, skin, and respiratory diseases, and cancer

• Diagnosis is based on measuring body weight and determining the body condition score (BCS) by evaluating specific physical characteristics

• The most successful treatment plans are designed specifically for each patient and include BCS and weight monitoring, diet change and caloric restriction, and increasing physical activity

• Obesity involves long-term treatment and prevention to successfully manage weight, and the prognosis often depends on the patient’s response to treatment

A Closer Look: What is Obesity in Cats?

Obesity is a common, serious condition that measurably decreases a cat’s life expectancy and can lead to other serious diseases. Optimal treatment plans include professional guidance from a veterinarian, the use of less calorie dense diets, gradually decreasing the portion provided, and increasing physical activity. When the weight comes off and stays off, some effects of obesity are completely reversed. The outcome is better the sooner the condition is treated.

Risk Factors

Fatty tissue is responsible for the release of several hormones, and can act as an inflammatory organ. Conditions that obesity may lead to include:

• Diabetes mellitus (obese cats are four-times more likely to develop this) • Pancreatitis • Hepatic lipidosis 

• Joint Disease (including osteoarthritis, and injuries) • Skin Disease • Impaired cardiovascular health • Decreased lifespan

• Cancer • Oral, urinary, and gastrointestinal tract disorders • Respiratory disease

These secondary conditions have a wide range of variable symptoms including: 

• Increased thirst • Increased urination • Appetite loss • Lameness • Rashes • Coughing • Sneezing

Possible Causes

While the main cause of obesity is the imbalance between caloric intake and energy output, factors that can increase the risk of developing obesity include: 

• Increased age • Physical inactivity • Food type and feeding habits • Genetics

In rare cases, weight gain is associated with a separate underlying condition like hypothyroidism. In these cases, the underlying condition must be addressed in tandem with the obesity in order for symptoms to resolve. Note: conditions contributing to unexplained weight gain in cats are rare. The vast majority of cases of obesity in cats are a simple imbalance of caloric input vs. output.

Main Symptoms

The primary symptoms of obesity in cats are

• Excess body weight • High BCS score (top 25% of the scale or higher)

• A layer of fat over the ribs and backbones, making them more difficult to find and feel

• Obvious rounding of the abdomen when viewed from the top or sides • No visible waist when viewed from the top or sides

Obese cats also typically become less physically active and are slower to get up and get moving. They are often less athletic and struggle to jump or climb. Several other symptoms may be evident in obese pets but stem from the secondary diseases that are caused by or exacerbated by obesity.

Testing and Diagnosis

Determining a cat's body condition score (BCS) is the best way to determine if a pet is obese. A BCS is a weight score usually out of 9 points and uses the look and feel of the pet’s ribs, waistline, and abdomen to determine the overall percentage of body fat. A score of 5/9 is an ideal body weight, whereas a score >7/9 is considered obese. A cat with an ideal body should have ribs that are easily palpable, a slight hourglass figure near the waistline, and a tucked-up appearance to the abdomen. A similar 5-point scale is also used by some practitioners. 

Cats also have a primordial pouch (a pouch of loose skin and fat) that hangs down from their lower abdomen. This structure is normal in all cats who carry the trait, and is not to be confused with excess fat. 

Additional diagnostics for obese cats include a thorough physical exam, blood work, and urinalysis in order to rule out other conditions and have a better understanding of overall health status.

Steps to Recovery

Treatment for obesity is targeted at weight reduction by increasing the number of calories burned and decreasing the number of calories consumed. Strategies include: 

• Feeding foods with lower calorie density • Gradually reducing portions • Increasing physical activity

• Monitoring weight and BCS

Loss of 1-2% of body weight per week is a healthy pace for weight loss. Both short-term and long-term weight loss goals are best for the best success. Weight loss in obese pets is a slow process and it may take several months to achieve a healthy body weight. Prognosis depends on the starting BSC of the patient, and response to treatment.

Prevention

Preventing overeating by strictly controlling portions is the best way to prevent obesity. Encouraging daily physical activity, and monitoring body weight and eating habits also.

Is Obesity Common in Cats?

Obesity is very common in cats

Typical Treatment

• Change in diet • Caloric restriction • Increased exercise/activity