How to help your dog lose weight

The plan in 7 steps

1. Check the shape. Feel the ribs and look for a waist.
2. Pick a target weight. Ask your vet, or use the calculator.
3. Feed for the target weight. Not for today's weight.
4. Weigh the food. A kitchen scale beats a scoop.
5. Count the treats. Keep them small and few.
6. Weigh your dog every week or two. Adjust if the scale stops.
7. Keep it off. Do not go back to the old portion.

Why it is worth it

You are not alone. In a 2022 survey of US vet clinics, 59% of dogs were overweight or obese. Many of their owners thought their dog was a normal weight.

Weight matters for a long, happy life. In a lifelong study of Labradors, each dog was paired with a littermate. One of each pair ate 25% less than the other and stayed leaner. The leaner dogs lived longer, by close to two years, and got arthritis later. In another study, owners said their dogs had more energy and less pain after they lost weight.

1. Check the shape

The scale alone does not tell you if your dog is overweight. Frame size differs, even in one breed. Vets judge the body shape. Put your flat hands on the ribs. On a lean dog, you feel them easily under a thin layer. Look from above. A lean dog has a waist behind the ribs. The 1-minute overweight check walks you through it.

2. Pick a target weight

Your vet can give you a healthy target weight. If you do not have one, use the dog's shape. Each step up the scale is about 10% extra weight. A round dog is often about 20% over a healthy weight. So a round dog that weighs 80 lb may need to get to about 67 lb.

3. Feed for the target weight

This is the step that does the work. Feed the amount for the weight your dog should be, not the weight it is now. Feeding for the current weight keeps the current weight.

The numbers on the bag are a start, but they are often too high for a dog that needs to lose weight. They are made for active dogs at a healthy weight. See the daily portion for a round 80 lb dog, then try your own dog.

A weight-loss food can help your dog feel full on less. In a 2010 study, obese dogs on a food high in protein and fibre lost more weight and more fat. If your dog seems hungry all the time, read why your dog is always hungry.

4. Weigh the food

Scoops are not accurate. In a 2019 study, owners who measured dry food with a cup or scoop were off by as much as 152%. Small portions were the hardest to get right. Weigh one level scoop of your dog's food on a kitchen scale once. Then you know what your scoop really holds. Or weigh every meal, which is even better.

5. Count the treats

Treats, chews and table scraps can undo a diet. Vets often say treats should be no more than 10% of what a dog eats in a day. Break treats into tiny pieces. Your dog cares how often, not how big. Or use some of the day's kibble as treats. The dog treat calculator shows how many treats fit in a day.

6. Weigh your dog every week or two

A safe pace is about 1% of body weight a week. Vets allow up to 2%. For an 80 lb dog, 1% is just under 1 lb a week, or about 3 lb a month. Getting from 80 to 67 lb takes about four months. Slow is fine. Slow is safe.

Weigh at the same time of day, on the same scale. Small dogs can be weighed by holding them on a bathroom scale and taking away your own weight. Many vet clinics let you use their scale for free.

If the weight has not moved in 2 to 3 weeks, check the treats and the scoop first. Then cut the daily food by about a tenth. Ask your vet if it still does not move.

7. Keep it off

This is where many dogs slip. In a follow-up study, about half of dogs that lost weight gained it back. Dogs that stayed on a weight-control food regained less. When your dog reaches the target, raise the food a little at a time. Keep weighing your dog once a month.

What about walks?

Walks are good for your dog's joints, heart and mood. But food matters much more for weight loss. A walk burns less than most owners think, and one large treat can cancel it. Change the food first. Then add walks slowly, as your dog gets lighter and finds moving easier.

When to see your vet first

• Your dog is very heavy, or has more than about 20% to lose.
• Your dog gained weight fast without eating more.
• Your dog seems tired, cold, thirsty, or short of breath.
• Your dog has a health problem or takes medicine, such as steroids.

A slow thyroid (hypothyroidism) and Cushing's disease can cause weight gain. They need a vet's treatment. A diet alone will not fix them.