Obesity is the most common nutritional disorder in dogs, and the most consequential. Overweight dogs develop arthritis earlier, tolerate heat worse, face higher anaesthetic risk, and are more prone to diabetes and certain cancers. A landmark lifetime study of Labradors found that dogs kept lean lived roughly two years longer than their overweight littermates, and showed signs of arthritis years later.
Two years. From portion control.
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Step one: an honest assessment
Weight alone tells you little. Use body condition instead.
Ribs. Run your hands along the ribcage with flat palms. You should feel each rib easily, with a thin covering of fat over them — like the back of your hand. If you have to press to find them, your dog is overweight.
Waist from above. There should be a visible inward tuck behind the ribcage. A straight or bulging outline is too heavy.
Abdominal tuck from the side. The belly should slope up from the ribcage towards the hind legs, not run parallel to the ground.
Most people underestimate their own dog by a full grade. Take a photo from directly above and from the side, and judge the photo. It is more honest than the dog in front of you.
Step two: rule out medical causes
Before dieting, consider a vet check — particularly for a dog who gained weight without a change in feeding, or who also has hair loss, lethargy, heat-seeking, excessive thirst or a pot-bellied appearance.
Hypothyroidism and Cushing’s disease both cause weight gain and neither responds to eating less. Testing is straightforward and it is worth ruling them out before six frustrating months.
Step three: work out the actual target
Your vet can estimate an ideal weight from breed, frame and body condition. A reasonable rule of thumb for a dog at a body condition score of 7 out of 9 is that they are carrying about twenty percent excess.
Safe rate of loss: one to two percent of body weight per week. Faster is not better — rapid loss costs lean muscle, and in extreme cases carries real metabolic risk.
For a 30kg dog who should be 25kg, that is roughly three to five months. Plan for that, not for six weeks.
Step four: count the calories
This is the part people skip, and it is the part that works.
- Find the kcal figure on your dog’s food. It is on the bag, usually per kilogram or per cup
- Ask your vet for a daily calorie target based on ideal weight, not current weight
- Weigh the food on kitchen scales. Measuring cups are wildly inaccurate — studies have found errors of up to 80 percent between people using the same cup
- Subtract the calories from treats, chews and extras from the daily total. Do not add them on top
A dental chew can be 70 to 100 calories. A pig’s ear can be 150. For a small dog, that is a quarter of the day’s food in one chew.
Step five: make less food feel like more
A hungry dog is a miserable, vocal, bin-raiding dog. The trick is volume and time, not quantity.
- Add low-calorie bulk. Green beans, courgette, or plain tinned pumpkin stirred into the bowl adds volume for almost no calories
- Switch to a food with higher fibre and protein. Veterinary weight-loss diets are formulated for exactly this: fewer calories per gram, with enough protein to protect muscle and enough fibre for satiety
- Slow the meal down. A meal that takes fifteen minutes satisfies far better than one that takes forty seconds
- Split into three or four meals
Outward Hound Fun Feeder Slo Bowl
A maze bowl that turns thirty seconds of eating into ten minutes of work. One of the cheapest and most effective things you can add to a weight-loss plan, because the dog feels fed.
Food-dispensing toys do the same job and add mental work, which tires a dog in a way that does not stress sore joints.
KONG Wobbler Treat Dispenser
Holds a full meal of dry food and releases it gradually as the dog nudges it. Uses food you have already counted, so the enrichment is free in calorie terms.
Step six: exercise, carefully
Exercise matters less than diet for weight loss — you cannot outwalk a bad portion size — but it matters enormously for keeping muscle.
For a heavy dog, start gently. Extra weight plus sudden hard exercise is how cruciate ligaments tear.
- Build duration before intensity
- Swimming and hydrotherapy are excellent, being non-weight-bearing
- Several short walks beat one long one
- Sniffing walks tire a dog mentally with minimal joint load
- Avoid hard ball chasing with an unfit, overweight dog
Step seven: get everyone on side
Weight-loss plans fail in households, not in dogs. Someone is feeding the dog.
- One person in charge of the daily measure
- A written list on the fridge of what everyone has given
- A rule about table scraps that the whole family has actually agreed to
- Neighbours told, if your dog visits them
Weigh monthly
Most vets will let you use the waiting-room scales for free, and it takes two minutes. Track it. Losses of one to two percent a week mean you are on course; no change over a month means the calories are still too high, usually because something uncounted is going in.
And when your dog reaches target, do not go straight back to the old portion. Recalculate for the new weight, then adjust to hold it steady.
