Canine obesity

Symptoms an owner can spot at home

• Body condition score (BCS) ≥ 6/9—ribs hard to feel under a layer of fat, waist no longer visible from above
• Reduced stamina on walks, panting earlier than peers
• Reluctance to jump, climb stairs, or play
• Visible fat pads at the tail base, over the spine, and along the flanks

When to see a vet

• Before starting any weight-loss plan, to rule out endocrine causes (hypothyroidism, hyperadrenocorticism)
• Rapid unexplained weight gain—not all weight gain is dietary
• Difficulty breathing, exercise intolerance, or collapse
• Mobility loss that does not improve once weight comes off

What it is

Obesity is now classified by WSAVA and AAHA as a chronic disease, not a cosmetic problem. Excess adipose tissue is metabolically active—it produces inflammatory mediators that contribute to osteoarthritis, insulin resistance, certain cancers, urinary disease, and shortened lifespan. A multi-decade prospective Labrador study found that dogs kept lean lived a median of 1.8 years longer than littermates fed ad libitum.

Body Condition Score (BCS) on the 9-point scale is the standard clinical assessment: 4–5/9 is ideal, 6–7/9 is overweight, 8–9/9 is obese. The score is hands-on (ribs, waist, abdominal tuck) and far more reliable than the scale alone, which cannot distinguish fat from muscle.

How vets diagnose it

Diagnosis is the BCS plus a weight history. Vets calculate a target weight, then a daily calorie target—typically the resting energy requirement (RER) of the target weight, sometimes restricted further for stalled cases. Endocrine screening (T4, low-dose dexamethasone suppression) rules out the small subset of cases where obesity is secondary to disease.

Treatment overview

Editorial overview only—your vet builds the plan. Effective weight loss combines: a measured daily calorie target (gram-weighed, not eyeballed); a therapeutic weight-loss diet (high protein, high fiber, controlled fat) to preserve lean mass and satiety; structured low-impact exercise; and monthly weigh-ins to titrate. Realistic loss is 1–2% of body weight per week—faster causes muscle loss.

What buyers can do

• Weigh food in grams on a kitchen scale. Volume measures (cups) routinely over-deliver calories by 20–80%.
• Switch to a therapeutic weight-loss food on vet recommendation; standard "light" foods are often only modestly reduced in calories.
• Account for treats—they should never exceed 10% of daily calories. Use single-ingredient freeze-dried protein or vegetable pieces (green beans, carrots).
• Use puzzle feeders, lick mats, and snuffle mats to slow intake and add enrichment without adding calories.
• Increase low-impact movement (sniff walks, swimming) gradually; aggressive jogging on an unfit obese dog risks orthopedic injury.