How to Help Your Cat Lose Weight

📅 December 30, 2020 👁 2644

📝 Summary

Obesity crosses species — and it harms a cat's heart, lungs, joints, and lifespan. The plan is simple: 'eat less, move more,' guided by a calorie formula and a safe, slow pace of about 1% of body weight lost per week.

Keywords: cat weight loss obese cat BCS score cat diet

1 Body Condition Score

Before dieting, know what ‘overweight’ means. The most used tool is the Body Condition Score (BCS), which comes in two scales: 1-5 (with 3 ideal) and 1-9 (with 5 ideal). The higher the score, the heavier the cat.

2 Why Obesity Hurts

Excess weight strains the heart (rapid breathing, irregular rhythm, enlarged left heart, even sudden death), weakens the lungs (labored breathing, open-mouth breathing, oxygen loss), and deforms bones and joints (pain, lameness, disability). It also invites diabetes, lower urinary tract syndrome, osteoarthritis, poorer quality of life, and a shorter life.

3 Diet: Calories and Portion

Start with the resting energy requirement: RER = 70 x (weight in kg)^0.75. A 5 kg indoor cat needs about 234 kcal/day to hold weight; an overweight cat eats less than that and adjusts as it slims. Multiply RER by a factor: neutered active adult 1.2, intact active adult 1.4, inactive/easy-weight-gain cat 1.0, weight-loss cat 0.8, weight-gain cat 1.8, kitten 0-4 months 2.5, 4 months-1 year 2.0. Total energy = factor x RER. Divide by the food’s energy density (on the bag) to get the daily grams. Example: a 10 kg neutered indoor cat losing weight needs 0.8 x 70 x 10^0.75 / 3.8 ≈ 83 g/day, split into two meals of about 42 g. Never let weekly loss exceed 1% of body weight — slow and steady wins.

4 Exercise

More movement burns extra calories. In a two-level home, put the litter box on one floor and food and water on the other to force walks (skip this if the cat has urinary issues). Lure it between floors with tiny food rewards, play with a wand or laser to bond while burning energy, and — for bold cats only — try a leashed stroll.

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