Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: Over half of dogs in the US are estimated to be overweight or obese, which shortens life and worsens arthritis, breathing problems, and diabetes risk. A successful plan starts with your vet calculating a target weight and daily calories. Prescription weight-loss diets are designed to keep dogs full and well-nourished on fewer calories, which is safer than simply feeding less of a regular food. Aim for gradual loss, often about 1–2% of body weight per week.
Why not just feed less?
- Cutting a regular food too much can shortchange protein, vitamins, and minerals
- Prescription diets add fiber, protein, and nutrients to keep dogs satisfied
- “Light” and “healthy weight” retail foods vary widely in calories
A safe plan
- Vet exam and body condition score
- Calculated calorie target and food amount
- Measure food with a kitchen scale
- Treats under 10% of calories, and use low-calorie options like green beans
- Regular weigh-ins, with plan adjustments every few weeks
- Increase activity gradually
Tips for success
- Everyone in the house follows the plan
- Use food puzzles to slow eating
- Replace some treats with play or praise
What to avoid
- Crash diets
- Human diet foods and supplements
- Free-feeding
Sources
- AAHA Nutrition and Weight Management Guidelines for Dogs and Cats. 2021
- Kealy RD, et al. Effects of diet restriction on life span and age-related changes in dogs. JAVMA. 2002
- Association for Pet Obesity Prevention: Pet obesity survey
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.