A dog's weight can swing between vet visits for ordinary reasons, including seasonal activity changes, different scales, uncounted treats, a change in who feeds them, and normal hydration variation. It can also swing because something medical is happening. Unexplained weight change in either direction is a reason to book an appointment, not a reason to adjust portions and wait.
Start by Ruling Out the Measurement
Before treating a number as a fact about your dog, check that it is a fact about your dog.
Veterinary scales are calibrated, but not all readings are taken the same way. A wriggling dog, a lead still attached and held taut, a different scale in a different room, or a weigh in straight after a large meal and a long drink can each move the figure. A ten kilogram dog who has just eaten and drunk can read several percent heavier than the same dog first thing in the morning.
Ask for readings to be taken consistently: same scale where possible, at a similar time of day, before rather than after a meal. Ask for the numbers to be written down with dates, and keep your own copy. A single reading is an anecdote. A series is data.
The Ordinary Explanations
The treat audit is the single most productive exercise on that list. Ask every member of the household to write down everything they give the dog for seven days, including training rewards, chews, table scraps and the last spoonful from a bowl. Households routinely discover that treats account for a quarter or more of daily calories, which is far above the ten percent that is generally considered reasonable.
Weight Is the Wrong Metric on Its Own
A number on a scale conflates fat, muscle, water and gut contents. Two dogs at identical weights can be in completely different condition, and one dog can lose fat and gain muscle while the scale barely moves.
This is why veterinary practices score body condition and muscle mass alongside weight. Body condition scoring assesses fat cover by feel over the ribs, spine and hips, and by looking at the waist and abdominal tuck from above and from the side. Muscle condition scoring is separate and assesses whether muscle is being lost, which matters particularly in older dogs and in several disease processes.
A senior dog can hold a steady weight while losing muscle and gaining fat. The scale reports no change. The dog has changed considerably. Ask for both scores at every visit and ask for them to be recorded.
When a Swing Is a Medical Question
This is the part that matters most, and it is the reason this article does not contain a weight loss plan.
Unexplained weight loss in a dog who is eating normally is a significant sign. So is weight gain that does not track with intake. Both belong to long lists of possible causes spanning endocrine, gastrointestinal, renal, cardiac, dental and other systems, and several of those causes are treatable when found early and considerably less so when found late.
Contact your veterinarian promptly if your dog has lost or gained more than about five percent of body weight without a change you can account for, if weight is changing alongside altered thirst, appetite or urination, if there is vomiting, diarrhoea, coughing, lethargy or exercise intolerance, if the abdomen looks distended, or if you can feel ribs or spine becoming prominent. A dog losing weight while eating well is not a dog who needs less food, and a dog gaining weight on a stable ration is not simply lazy. Both descriptions fit real diseases.
Do not put a dog on a reduced ration to correct an unexplained change before it has been investigated. Restricting intake in a dog whose weight is moving for a medical reason can obscure the picture and can do harm. The World Small Animal Veterinary Association's global nutrition guidelines treat nutritional assessment as a routine part of every clinical examination, which is the framing to bring to the conversation.
What to Do Between Appointments, and What Not to Change
Keep a simple record. Weigh at home if you can, monthly, on the same scale and under the same conditions. Small dogs can be weighed by holding them on bathroom scales and subtracting your own weight. Many practices will let you use their scales between appointments without a consultation, and most are happy to.
Measure food rather than estimating it, ideally by weight rather than by volume, because scoop packing varies enormously. Log treats. Photograph your dog from above and from the side every month, in the same spot, because gradual change is invisible day to day and obvious in a series of photographs.
Bring all of that to the appointment. A year of monthly weights and a treat log turns a vague concern into something a vet can work with in ten minutes.
Owners often respond to a weight swing by changing food, and it is worth being clear about what that does and does not achieve.
Recipes differ in calorie density and macronutrient balance, and those differences are real. The Turkey Reduced Carbohydrates recipe is an example of a recipe designed around a lower carbohydrate share, built on turkey with sweet potatoes, green beans, broccoli and dried kelp, and served as eight ounce bars. Its own product page states plainly that it is not a veterinary prescription diet.
That description is what the recipe is. It is not a treatment for a weight problem and it is not a diagnostic step. A reduced carbohydrate recipe does not address why a dog's weight is moving, and choosing one instead of investigating is the wrong order of operations. Note too that the brand publishes no calorie content, guaranteed analysis or feeding directions in its product listings, so you cannot compare recipes on energy density from published data. Ask customer service for those figures if you need them.
Frequently Asked Questions
How much weight change is normal between visits?
For a healthy adult dog at a stable activity level, very little. Variation of a percent or two reflects measurement conditions. More than around five percent without an explanation is worth a call.
Should I weigh my dog before or after a meal?
Before, and ideally at a consistent time of day. Consistency matters more than which time you pick.
My dog gained weight after being neutered. Is that expected?
Energy requirements typically fall after neutering, so weight gain is common when portions stay the same. It is still worth discussing at the next appointment so the new ration is set deliberately rather than by drift.
Can stress or a house move change my dog's weight?
Yes, in either direction and usually temporarily. If it persists beyond a few weeks, treat it as unexplained and have it looked at.
Is a home scale accurate enough?
For tracking trends, yes, provided you use the same scale and method every time. For an absolute figure your practice's scale is better. Trends are what you are after.
Related reading: My Perfect Pet Turkey Reduced Carbohydrates: What Does a Reduced Carb Dog Food Actually Mean?