Will Neutered Cats Always Gain Weight? A Comprehensive

After neutering, cats may experience several physical changes, and these changes can all act as triggers for weight gain.

Lower Basal Metabolic Rate

Scientific research has shown that the basal metabolic rate of unneutered cats is up to 30% higher than that of neutered cats. This means that even when they are at rest, unneutered cats can burn more calories than neutered cats. This highlights the significant energy expenditure associated with the reproductive system, as the process of producing sperm and eggs requires a considerable amount of energy. With a lower basal metabolic rate, if the amount of food and exercise remains the same, the energy intake can exceed the expenditure, leading to potential weight gain.

Hormonal Changes

Following neutering, there is a noticeable decrease in hormonal levels in cats, along with disruptions and adjustments in the endocrine system. Hypothyroidism can occur, and these changes can all contribute to weight gain. The first three months after neutering often involve hormonal imbalances, so it's important to monitor weight during this time. Cats will eventually adjust to a balanced state, but some may still find it challenging to lose weight, even with controlled diets, likely due to hormonal weight gain.

To put it simply, a neutered cat's lifestyle changes from play, reproduction, and rest to a more sedentary one, with reduced energy expenditure. This natural shift can lead to weight gain.

There have been studies conducted to understand this phenomenon better. Researchers followed 49 neutered cats and 11 unneutered cats (aged between 1.5 and 11 years) for 12 months, observing their weight gain under a freefeeding system. The results were:

1. After 12 months, the neutered cats experienced an average weight increase of 31%, compared to just 3.1% in the unneutered cats over the same period.

2. The body fat percentage of the neutered cats increased by an average of 40%.

3. Unneutered cats were more likely to control their own food intake, while neutered cats tended to finish all the food provided. To maintain a healthy weight after neutering, it may be necessary to reduce calorie intake by about 30%.

While weight gain after neutering is a real concern, it's not a universal outcome. Some cats may gain weight significantly, while others may not show much change at all.

If your cat is showing signs of weight gain, here's how you can help control its weight:

Control the Diet

During the postneutering period, cats might overindulge. If you've been providing an "allyoucaneat" buffet, it's time to switch to timed and measured feedings. Whether you feed dry food or canned, aim to reduce the daily intake to about 60% of the usual amount. This means lowering the calorie intake to around 40 to 45 kcal per kilogram of body weight, compared to the traditional recommendation of 70 to 90 kcal per kilogram.

Highcalorie treats should be kept out of reach. Additionally, consider investing in a cat weight scale to monitor your pet's weight weekly. If there's a significant increase, adjust the daily food intake accordingly.

Encourage Physical Activity

Engage your cat in play sessions with toys like laser pointers or small mouse toys to stimulate movement. While some owners find chubby cats adorable, obesity can lead to a host of health issues in cats, including diabetes, fatty liver, joint diseases, tumors, urinary tract problems, and skin conditions. Prioritize your cat's health and happiness by maintaining a healthy weight.

During this critical period after neutering, it's advisable for cat owners to use scientific methods to control their pet's weight. If weight management becomes challenging, don't hesitate to consult a veterinarian for professional advice. Overweight cats may require medical intervention to shed excess pounds.