Overweight in Dogs – More Than a Cosmetic Issue

Approximately 40–60% of dogs in the Western world are estimated to be overweight or obese. This is supported by several epidemiological studies and mirrors the broader trend in Western societies, where obesity has also become a widespread health concern among humans. Unfortunately, overweight and obesity are not merely cosmetic problems—they are significant health issues. Excess body fat has a mechanical impact on the dog’s musculoskeletal system, as it represents additional weight the dog must carry, placing increased strain on the joints. This can lead to orthopedic disorders and respiratory difficulties. In addition, excess fat tissue has physiological effects: it produces pro-inflammatory metabolic compounds and disrupts hormonal balance, which may contribute to diabetes mellitus, insulin resistance (and potentially increased dementia risk), as well as cancer. Studies have also shown that overweight dogs experience reduced quality of life, as they are often less energetic than their lean counterparts and may suffer from pain. A long-term study further demonstrated that even mildly overweight dogs have a shorter life expectancy compared to dogs at an ideal weight. There are the…

But what does a lean dog actually look like? Unfortunately, many dog owners have a distorted perception of what constitutes a healthy body condition. This is hardly surprising when overweight dogs repeatedly win breed competitions at major dog shows. In a dog of ideal weight, the ribs should be easily palpable. When the dog is moving, it is perfectly acceptable to faintly see the outline of the ribs beneath the coat. There should be only a minimal fat covering over the ribs. The waist should be clearly visible when viewed from above, and the abdomen should show a distinct tuck when viewed from the side. Naturally, some breeds with heavy coats or excess skin cannot be assessed in exactly the same way. In such cases, consulting a veterinary professional may be advisable. If you own an overweight dog—or follow debates on social media about canine obesity or weight-loss diets—you have likely heard the statement: “An overweight dog just needs to eat less. It’s that simple.” In reality, it is not that straightforward.

The causes of obesity are multifactorial. One of the primary contributors (pun intended) is an imbalance between energy intake and energy expenditure—meaning the dog consumes more energy than it burns. However, because energy requirements are influenced by many factors, it is not always easy for owners to determine how much their dog should eat. Requirements depend on sex, neuter status, age, body composition, and activity level. Even dogs that appear identical according to these parameters may have significantly different metabolic rates and therefore very different energy needs. Another extremely important factor—one that few dog owners are aware of—is the composition of the diet itself. This is not just about the total energy (calories), but about which macronutrients provide that energy. There are three energy-yielding macronutrients: protein, fat, and carbohydrates (including starch and sugar). From an anatomical and physiological perspective, dogs are adapted to a diet rich in protein and fat. Nevertheless, many commercial dog foods contain large amounts of starch and sugar. This can be problematic, particularly for dogs that need to lose weight or are prone to gaining weigh…

The issue centers around the hormone insulin, which is released when large amounts of starch and/or sugar are broken down into glucose, leading to a rapid rise in blood sugar levels. Insulin is an anabolic hormone with vital functions. It clears glucose from the bloodstream—preventing potential damage to internal organs—and transports nutrients into cells where they are needed. Insulin acts like a key, unlocking cells so they can absorb nutrients from circulation. When insulin is active, glucose utilization for energy increases, and triglyceride (fat) synthesis within cells is promoted. This leads to the formation of fat deposits—energy reserves for “hard times” that, for most dogs, will never come. In addition to promoting fat storage, insulin also inhibits the body’s ability to use free fatty acids as an energy source. In other words, the body cannot effectively burn fat when insulin levels are high. If a dog is fed a diet high in starch and/or sugar, insulin levels may remain elevated for much of the time. For overweight dogs—or dogs that gain weight easily—it is therefore important not only to monitor total energy intake, but also to consider the ingredients in the diet. Avoid…

Returning to the claim: “An overweight dog just needs to eat less.” Simply reducing the daily ration of a complete diet is not always the solution. Some dogs have such low energy requirements that they would need to consume very small portions, putting them at genuine risk of insufficient intake of essential nutrients, including amino acids, minerals, vitamins, and fatty acids. These dogs require a specially formulated diet that is low in energy but highly concentrated in essential nutrients. Finally, remember that general information about canine nutrition—such as presented here—applies to healthy, adult dogs without specific medical conditions. Dogs are individuals, and the above information may not necessarily apply to your dog. Always consult a well-qualified canine nutrition professional if you have any doubts about feeding practices.

Litterature

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