Puppy food for underweight dogs
An underweight puppy needs its cause identified before its food is changed — a fussy eater, a recent illness, worming status and simple genetics can all look the same on the outside, and only some of them are solved by a more calorie-dense food. Once a vet has ruled out an underlying problem, a nutrient-dense puppy food fed to the higher end of its guide is usually the practical next step.
Why the cause matters before the food does
A puppy that is thin because it is a naturally lean breed, going through a growth spurt, or simply a picky eater needs a different response to one that is thin because of worms, illness, or a food that does not agree with it. Changing food without knowing which of these applies can mask a problem rather than fix it.
If your puppy is losing weight, has not gained as expected at vaccination or weigh-in appointments, or seems lethargic alongside being thin, that is worth a vet visit before anything else — worming status in particular is worth checking, since a heavy worm burden is a common and treatable cause of a puppy failing to gain weight properly.
What to look for once other causes are ruled out
A calorie-dense puppy food, with a named meat protein high on the ingredients list, gives more energy per bowl than a standard recipe, which helps a genuinely underweight puppy gain without needing to eat an unmanageably large volume of food. Puppy-specific recipes are also formulated to support healthy growth rather than just adding weight.
Feeding at the higher end of the pack's guide for your puppy's current weight, split across several smaller meals rather than one or two large ones, tends to work better for a puppy that struggles to eat much in one sitting.
Encouraging a fussy or reluctant eater
Warming wet food slightly, or adding a small amount of warm water to dry kibble, can make food more appealing to a puppy who is eating reluctantly, and feeding in a calm, quiet spot away from other pets sometimes helps too. These are worth trying alongside, not instead of, working out why the puppy is underweight in the first place.
Persisting fussiness, especially alongside weight loss, is a reason to go back to your vet rather than simply trying food after food, since an underlying cause will not resolve on its own no matter how appealing the bowl is.
What we stock
Everything below is in stock with us, priced with delivery worked out, and packed and posted by hand in the UK.
Forthglade Cold Pressed Small Dog Turkey
Cold-pressed grain-free dry food for small dogs and puppies, built on turkey
£16.99
Harringtons Just 6 Dry Dog Food Lamb
Grain-free lamb dry dog food in 2KG and 12KG sizes, with size-specific formulas
From£13.99
Harringtons Adult Dog Salmon & Potato
Complete salmon and potato dry dog food with 21% protein in a 1.7KG bag
£6.25
Lily's Kitchen Dog Lean Machine
Lily's Kitchen's lowest-calorie wet recipe for adult dogs, in a 150G foil
£1.69
Forthglade Cold Pressed Natural Turkey
Cold-pressed turkey kibble for dogs from 2 months, soft enough to mix with water for young pups
£45.99
Forthglade Cold Pressed Grain Free Salmon
Cold-pressed grain-free dry food for dogs, built on fresh and dried salmon
From£16.99
Forthglade Cold Pressed Grain Free Duck
Cold-pressed grain-free duck food with fruit and botanicals, in two bag sizes
From£16.99
Forthglade Cold Pressed Grain Free Chicken
Cold-pressed grain-free chicken food with fruit and botanicals, in three bag sizes
From£16.99
Burns Puppy Junior Original Chicken Rice
A complete puppy and junior food with dried chicken 31% and controlled fat at 15%
From£14.99
Forthglade Complete Meal Lightly Baked Turkey
A lightly baked complete dry food, 50% turkey, for adult dogs of any breed
From£12.49
Forthglade Complete Meal Lightly Baked Chicken
A grain-free complete dry food for adult dogs, lightly baked and built on 50% chicken
From£12.49
Forthglade Complete Meal Lightly Baked Lamb
A lightly baked complete dry food, 50% lamb, for adult dogs of any breed
From£12.49
Common questions
- How do I know if my puppy is underweight?
- You should be able to feel ribs easily with a light covering of flesh, and see a waist from above once your puppy is a few months old. A puppy where ribs, spine and hip bones are very prominent, or that is not gaining weight as expected, should be checked by a vet.
- Should I just feed my underweight puppy more?
- Not without knowing why they're underweight first. Worms, illness or an unsuitable food can all cause weight loss or poor gain, and a vet check helps rule these out before you simply increase the amount fed.
- Is a high-calorie puppy food safe for a growing dog?
- A calorie-dense recipe formulated specifically for puppies is designed to support healthy growth, unlike an adult food. Once your vet has confirmed there's no underlying cause for the low weight, feeding a puppy-specific recipe to the upper end of its guide is a reasonable approach.
- How long does it take an underweight puppy to reach a healthy weight?
- This varies a lot depending on the cause and the individual puppy, and is best judged with your vet through regular weigh-ins rather than a fixed timescale. Steady, gradual gain is a better sign than a sudden jump in weight.
Related
Written by Matt Garnett, who runs Giddy Pets and is a lifelong pet owner — not a vet. This is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your animal. How we write these guides.