It’s not just about quantity: weight control and pet food

When it comes to controlling obesity in pets, there’s a need to focus more on the energy density and nutrients of specific diets rather than just seeking to reduce feeding volume.

Obesity is a disease of prosperity that has also affected pets. A survey by the Association for Pet Obesity Prevention (APOP) found 59% of dogs and 61% of cats in the US to be overweight or obese. As in humans, obesity in pets can lead to serious health issues. Time to shed some weight. But how should this be approached?

Ways to make progress

Simply reducing the amount of food is not a solution. Progress in this field should incorporate specific weight-loss diets, but also a focus on careful monitoring of body condition score, as well as providing support for pet owners.

Using an existing product, such as an already available adult formula, and just adjusting the feeding recommendation to create a weight-loss diet doesn’t work. If you reduce the amount of a product by, for example, 20%, you not only reduce the calorie intake but also the intake of essential nutrients such as amino acids, fatty acids, minerals and vitamins by 20%. Therefore, simply reducing the ration of regular food over an extended period poses a serious risk of nutrient deficiency.

Nutrients versus calorie intake

Looking at the nutritional guidelines from the European Pet Food Industry Federation (FEDIAF), it becomes apparent that it considers animals with different energy needs in its recommendations. For adult dogs, there are nutrient recommendations based on 95 and 110 kcal ME/kg0.75, respectively, and 130 kcal ME/kg0.75 for growing dogs. These figures are guidelines and must be aligned with an animal’s individual metabolism, activity level and living conditions.

For a product designed for weight loss, a formulation with low calories but an increased nutrient-to-calorie ratio is ideal. The goal is to ensure weight loss through the breakdown of body fat, while preserving muscle mass and providing vital nutrients for health
and well-being.

There seems to be a significant challenge in the market, as commercial weight-loss pet foods often have a wide calorie range. According to a study in 2010, out of 44 examined weight-loss foods for dogs, the calorie content ranged from 217 to 440 kcal per cup.

Feeding recommendations

Weight-loss diets typically fall under “feed intended for particular nutritional purposes”, accompanied by indications for veterinary examination and diagnosis. Unlike regular pet foods, where feeding recommendations are often broad, the recommendations for weight-loss diets should be detailed to provide pet owners with meaningful guidance. It’s important to also consider treats and snacks in the daily ration.

Instructions on how to handle mixed feeding should also not be overlooked. Simply replacing half of the amount of wet food with the exact grams of dry food (which has a much higher nutrient density) inevitably leads to drastic overfeeding.

Body Condition Scores

Regular veterinary check-ups during weight loss are highly recommended to adjust the ration continuously and monitor the pet’s health. This is sensible since both weight gain and obesity, as well as unexplained weight loss, can be consequences of various diseases that need to be clarified beforehand.

A body condition score (BCS) system helps in this regard. Although there are breed-specific average values for the optimal weight of an animal, these serve as a general guideline. Whether an individual’s weight is within the ideal range must be considered in combination with the body structure.

There are numerous BCS that help categorize an animal’s weight status into various levels (overweight and underweight). Most often used is the 9-point BCS system designed in 1995, with updates in subsequent years. It includes an estimation of body fat, physiological body features and a percentage deviation from the ideal weight. The BCS system is an ideal reference and should be made available to buyers of weight-loss pet foods in an understandable format for monitoring their pet’s weight development.

Ingredients suitable for weight loss food

Lean muscle meat: Lean meat, such as chicken, provides an excellent nutrient base.

Protein isolates/hydrolysates: Proteins are essential for muscle maintenance. Protein isolates of plant and animal origin are a good way to increase the protein content of pet food without adding extra fats.

Omega 3/-6 oils: Although animal and plant ingredients already contain natural fats, adding an appropriate amount of omega 3/-6 oil blend ensures the complete coverage of essential fatty acids.

Fiber, e.g. cellulose: Fiber helps increase the volume of food without significantly contributing to the energy content. A higher volume of food supports the pet’s satiety and gives pet owners a positive feeding experience. Pet owners who feel their pet is hungry or receiving a noticeably smaller food portion are more likely to feed them snacks or treats.

L-carnitine: This additive is essential for fat metabolism, acting as a transporter of fat components to the mitochondria, where fat is burned. L-carnitine is also produced by the body itself.

Focus on fat and starch

A study in 2023 from the College of Animal Science and Technology, Beijing, evaluated that reducing energy density combined with the use of pea starch represented valuable concepts for supporting weight management and positively affecting the gut health of cats. The fat content and starch source directly impact the gut microbiome.

The presence of beneficial gut bacteria was significantly higher in the fat-reduced diet with pea starch as the carbohydrate base compared with control groups with higher fat content or corn starch as the carbohydrate source.

Additional support

What else can developers of weight-loss pet foods do to support customers’ pets effectively?

In addition to focusing on ingredients, correct nutrient calculation and specific feeding recommendations, there are tools that pet owners can use to support their pets on the weight-loss journey.

Pre-portioned meals tailored to daily activity levels (e.g. special breakfast, lunch and dinner portions) would be a helpful measure to avoid overfeeding. Such measures are best implemented by pet food companies offering pet food as individual rations, but a reduced version of this idea is also feasible for the general pet food industry.

Properly scaled measuring aids are also a great support for pet owners. In particular, measuring cups for dry food are often roughly scaled and show significant deviations during control weighing. Therefore, using a measuring cup with the smallest diameter or offering a ladle with an integrated scale would be beneficial.

Realistic training programs, a motivation app with rewards for pets and their owners, or food diaries immensely help customers and simultaneously strengthen trust and brand loyalty.

Julia Klischies

Pet Nutritionist
petfood-expert.com