How to Help Your Dog Lose or Gain Weight: A Body Condition Guide

Is My Dog Actually Overweight or Underweight?
Could Something Besides Food Be Causing the Change?
How Do I Help My Dog Lose Weight?
How Do I Help an Underweight Dog Gain Weight?
How Much Should I Feed for Weight Loss or Gain?
Does the Type of Food Matter for Weight Management?
Frequently Asked Questions
Sources

Start by checking your dog's body condition score, not just the number on a scale, because two dogs at the same weight can be in very different shape. If your dog is overweight, a safe weight-loss pace is about 1 to 2% of body weight per week, reached by measured portions and more activity.¹ If your dog is underweight, the fix is usually a controlled calorie increase and, first, ruling out a medical cause with your veterinarian. Either way, the diet change should be gradual and vet-guided, not a sudden overhaul.

Is My Dog Actually Overweight or Underweight?

Weight on a scale only tells part of the story. A 62-pound Labrador and a 62-pound Labrador mix can have completely different body conditions depending on frame size and muscle mass. That's why veterinarians use a Body Condition Score (BCS) instead of weight alone.

The Association for Pet Obesity Prevention (APOP) and most veterinary nutritionists use a 9-point BCS scale, with scores of 4 to 5 considered ideal, 6 to 7 overweight, and 8 to 9 obese; scores of 1 to 3 fall on the underweight side.² You can get a rough read at home with three checks:

Check	Underweight (1-3)	Ideal (4-5)	Overweight (6-9)
Ribs	Visible, no fat cover, may look prominent	Easy to feel with light pressure, not visible	Hard to feel under fat, or not felt at all
Waist (viewed from above)	Severe hourglass, hip bones prominent	Visible tuck behind the ribs	Little to no tuck, or a rounded back
Abdomen (viewed from the side)	Extreme abdominal tuck	Tucked up	Sagging or level with the chest

If your dog scores at either end, or if you're not confident reading the signs, ask your veterinarian to confirm the score at your next visit. It takes about thirty seconds and it's the single most useful number for deciding what to do next.

Could Something Besides Food Be Causing the Change?

Before changing anything about your dog's diet, rule out a medical cause with your veterinarian. This matters in both directions.

For unexplained weight gain, common contributors include hypothyroidism and Cushing's disease (hyperadrenocorticism), along with a slowing metabolism as a dog ages and, less obviously, a stressful or under-stimulating home environment.³ For unexplained weight loss, a veterinarian will typically check for intestinal parasites, dental disease that makes chewing painful, chronic conditions like kidney or liver disease, and anxiety or stress that suppresses appetite.⁴

A physical exam, bloodwork, and a review of exactly what and how much your dog currently eats (a written food diary helps here) let your vet confirm that diet and exercise changes are actually the right tool before you start.¹

How Do I Help My Dog Lose Weight?

Once your veterinarian has confirmed a diet-driven weight-loss plan is appropriate, the mechanics are straightforward, even if sticking to them takes discipline.

Weigh food, don't scoop it. A measuring cup is surprisingly inaccurate, and small daily overages add up over weeks. A kitchen gram scale lets you hit a precise daily target and adjust it in small increments as your dog progresses.¹

Keep treats to 10% of daily calories. This is the standard veterinary guideline: 90% of your dog's calories should come from their main meals, and no more than 10% from treats and extras combined.¹ If your dog needs 600 calories a day, that's a 60-calorie treat budget, which is easy to blow through with a handful of high-fat snacks and easy to stay inside with vegetables like carrots or green beans.

Choose a moisture-rich diet. Foods with higher moisture and protein content tend to help dogs feel fuller on fewer calories, and added hydration supports kidney and urinary tract function, which matters more in dogs carrying extra weight. Fresh, gently cooked food like A Pup Above is naturally higher in moisture than dry kibble; browse the full recipe lineup and compare their guaranteed-analysis and calorie information if you're looking for an option to rotate in.

Add exercise gradually. Start with short, frequent walks rather than one long session, especially for a dog that's been sedentary, and build up from there. Games like fetch or a gentle round of tug also burn calories without the joint stress of a long run. If your dog is significantly overweight, check with your vet before increasing activity, since extra weight puts real strain on joints.¹

As one veterinary nutrition team puts it: "Dogs may also experience muscle loss secondary to inactivity, which can make it even more challenging for them to move around."¹ That's why the 1 to 2% per week pace matters more than speed: a dog that loses weight too fast tends to lose muscle along with fat.

How Do I Help an Underweight Dog Gain Weight?

Gaining weight safely follows the same logic in reverse: rule out a medical cause first, then increase calories in a controlled, gradual way.

Increase calorie density, not just volume. Rather than simply feeding more of the same food, which can overwhelm digestion, look for a recipe with more protein and fat per serving. A recipe with more protein and fat per serving packs more calories into the same volume, so an underweight dog can take in more energy without needing a much bigger bowl.

Feed smaller meals, more often. Splitting a dog's daily calories across three or four smaller meals instead of one or two larger ones is easier on digestion and gives an underweight dog more chances to eat before they lose interest. This is especially useful for a dog recovering from illness, a recent rescue, or a naturally light eater.

Address palatability if appetite is the problem. Some dogs are underweight simply because they're not excited about what's in the bowl. Warming food slightly, or switching to a recipe with a stronger, more natural aroma, can help a picky or convalescing dog eat enough. If a poor appetite, rather than a high metabolism, is the real issue, our guide to feeding a picky eater covers that in more depth.

Go slow. Just as with weight loss, rapid weight gain isn't the goal. A gradual increase over several weeks, with your vet checking progress, is safer than trying to pack on pounds quickly.

How Much Should I Feed for Weight Loss or Gain?

There's no single calorie number that works for every dog: it depends on current weight, target weight, age, and activity level, which is why a veterinarian (or a validated calculator, such as APOP's free daily feeding calculator) should confirm the number before you commit to it.¹ ² As a starting framework:

Goal	Typical adjustment	Reassessment
Weight loss	Reduce daily calories, often by starting from current actual intake rather than the bag's suggested amount, then adjusting down	Re-weigh every 2 to 4 weeks; expect roughly 1-2% body weight lost per week
Weight gain	Increase daily calories gradually, split across more, smaller meals	Re-weigh every 2 to 4 weeks; adjust portions as your vet recommends
Maintenance (holding a target weight)	Feed to your dog's current, confirmed-healthy body condition score	Recheck BCS every few months, or after any diet change

Whichever direction you're headed, use the same feeding chart logic for portioning day to day. Our feeding amount guide breaks portions down by weight if you need a starting point before your vet fine-tunes it.

Does the Type of Food Matter for Weight Management?

It can, mostly through moisture content rather than any one format being inherently "better." Dry kibble is calorie-dense and low in moisture (typically under 12%), which makes portion control easier to get wrong with a measuring cup. Canned and fresh foods carry more water weight per calorie, so the same number of calories takes up more volume in the bowl, which can help a dog on a restricted diet feel satisfied on less energy. None of this makes one format unhealthy; the numbers just work differently, and either way, weighing the actual daily amount matters more than which bag it came from.

A Pup Above's recipes are gently cooked using a sous-vide method and made from human-grade ingredients, which is a different ingredient standard than conventional pet food regardless of moisture content. If you're weighing a switch as part of a weight-management plan, do it gradually over about a week, mixing the new food in with the old, since a fast switch is more likely to upset a sensitive stomach than to speed up results.

Frequently Asked Questions

How do I know if my dog is overweight or underweight? Feel along your dog's ribs and look at their waist from above. Ribs you can feel easily without pressing hard, and a visible waist tuck behind the ribcage, point to a healthy body condition score of 4-5 out of 9. Ribs that are hard to feel under a layer of fat suggest overweight; ribs, spine, or hip bones that are visibly prominent suggest underweight. When in doubt, ask your veterinarian to score it at your next visit.²

How much weight should my dog lose or gain each week? For weight loss, veterinary guidance points to roughly 1 to 2% of body weight per week as a safe pace, with closer to 0.5% recommended for dogs that are significantly obese.¹ For weight gain, there's no single published rate, but the same principle applies: gradual and vet-monitored beats fast.

Can my dog still have treats while losing weight? Yes. The standard rule is that treats should make up no more than 10% of daily calories, with the remaining 90% coming from meals.¹ Lower-calorie options like plain carrots or green beans stretch that budget further than fatty commercial treats.

What if my dog won't eat enough to gain weight? First rule out a medical cause (parasites, dental pain, or illness are common culprits) with your veterinarian.⁴ If appetite itself is the issue rather than an underlying condition, warming food, choosing a more aromatic recipe, or switching to smaller, more frequent meals can help. Our picky eater guide goes deeper on getting a reluctant eater to finish a meal.

Do I need a special "diet" food to help my dog lose weight? Not necessarily. What matters most is the total calories your dog eats each day relative to what they burn, measured accurately with a kitchen scale rather than a scoop.¹ Some dogs do well simply eating their normal food in a smaller, weighed portion; others benefit from a lower-calorie-density recipe. Your veterinarian can tell you which fits your dog.

Should I switch my dog's food entirely, or just adjust portions? Start with portions, since that's the lower-risk, easier-to-reverse change. If you do decide to switch foods as part of a broader plan, transition gradually over about a week by mixing old and new food together, and keep your vet in the loop so the calorie math stays consistent through the switch.

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