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Pet Weight Loss Foods Need Special Qualities

It is commonly thought that pets can just be fed less of their regular food during a weight loss program. Unfortunately, this is not the case. Regular adult maintenance foods are generally lacking in the special needs qualities that are found in diet foods.

High Protein

In order to lose weight, a dieter must eat fewer calories than necessary to support ideal weight. This undernourished state requires that the body use the energy stored in fat. The switch to stored energy also requires that the body use proteins.

The amino acids in protein are used to make sugar to feed the nervous system and the heart muscle and are necessary to use fat energy. The storage form of protein is muscle, and dieters lose muscle as well as fat during a diet. Studies in humans, dogs and other animals confirm that weight loss foods that are high in protein decrease this muscle loss and increase fat loss during a diet.

Feeding dogs 39-40 percent of their calories in protein, and cats 46-50 percent of their calories in protein has proven to be effective for decreasing muscle loss. The animal also uses 25 percent of its own calories during the process of digesting the protein in food. This energy expenditure to digest protein aids in further weight loss.

Human subjects have found high protein weight loss diets to be more satisfying and consequently will voluntarily eat less food. Although not proven in cats and dogs, experimental evidence suggests the same satisfying effect of high protein diet pet foods.

High Fiber

As the stomach fills with food during a meal, it enlarges or distends. This “stretching” causes the release of hormones into the blood stream, from which point they travel to the appetite center of the brain, setting off the signals for fullness or satiation. This effect continues as food moves from the stomach and fills the intestines.

By increasing the amount of indigestible fiber in diet food, fewer calories can be fed while causing the same stomach and intestinal distension and releasing the same hormones. The brain receives a signal of satiation despite the ingestion of fewer calories. Human studies confirm this effect and animal studies are very suggestive. Owners report decreased begging behavior when pets are dieted on high fiber diets.

Low Fat

The purpose of a diet is to lose fat, so feeding excess fat makes little sense. Fat contains more than twice the calories per gram than protein and carbohydrates. The body does need fat, especially the essential omega-3 and omega-6 fatty acids, but more than the essential amounts only adds calories to the diet - 40 calories per teaspoon to be exact (no matter what kind of fat or oil!).

In addition to reducing the nutrient value of the meal, fat also reduces the size of each meal, and dieters don’t appreciate that. Additionally, fat only uses 2-3 percent of its own calories during digestion, leaving the rest of the fat to be absorbed and stored in the body!

Added Vitamins and Minerals

The dieting body can tolerate fewer calories than necessary for its ideal weight. The same is not true of vitamins and minerals. Limiting the calories of regular food also limits necessary vitamins and minerals. Fortifying diet food with vitamins and minerals ensures adequate intake of these nutrients despite the decreased meal size.

Regular pet foods do not meet any of the above qualities. In fact, animals that are dieting on adult maintenance formulas would suffer deficiencies in essential amino acids, vitamins, and minerals.

Over the counter weight control foods are no better. To begin, they are formulated for use without veterinary supervision. The 95 or so weight control foods available for cats and dogs meet few of the above requirements, so their calorie restriction is typically inadequate for successful weight loss. The protein content of these foods is rarely higher than regular food and the fiber content is variable. Few claim any vitamin or mineral fortification.



So what are the perfect diet foods for pets? For a serious weight loss program there are only two quality alternatives. 

The first is a veterinary formulated and approved weight loss diet. There are several brands to choose from. These products are designed to be convenient to use while addressing the needs of the dieting pet.

The second is a homemade diet that is specially formulated to meet these same demands. Although more expensive and less convenient, homemade diets are tastier and more satisfying than their commercial counterparts. An added benefit is that the extra expense and commitment required by the owner fosters greater compliance with the weight loss program. Homemade diets also allow for greater manipulation of ingredients to address the changing needs of the dieting pet.

If you are undecided, your veterinarian can help you chose the best alternative for you and your pet.  



Dr. Ken Tudor



Image: Emilia Stasiak / via Shutterstock


Comments  8

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  • cat diets
    03/01/2012 06:13am

    My cat is about 15. He has always been a thin cat, but now, although he eats well, he is becoming increasingly fragile. I feed him well, and he eats and drinks well. He now eats Fancy Feast daily. I don't want to feed him excessive fats due to worries about pancreatitis. He is not a sick cat; he is interactive, playful, talkative, loving, purrs, etc. He just seems to be an elderly cat. What are your recommendations about this issue? I realize he may be reaching the upper limit of life expectancy, but I want him to do well for as long as is reasonable or possible.

  • 03/01/2012 11:48am

    lefty, have you had a full blood panel done to rule out things like kidney disease?

  • Supplements
    03/01/2012 11:43am

    Does anyone have thought regarding vitamin supplements for a pet while dieting?

  • Homemade Diet
    03/01/2012 03:23pm

    Is there any recipe online or one that you recommend for the homemade diet? I really don't want to put my dog on prescription food. The pet food manufacturers of those products still put crap in it that I don't want my dog eating (i.e. gluten, by-products, etc). My dog currently weighs 25 pounds and should probably weigh around 15-18. Thanks!

  • Lefty
    03/01/2012 04:33pm

    Believe or not but older cats do not need special food unless they have an existing medical problem. In fact they often need more protein and fat to counter the sarcopenia (muscle loss) of the aging process. Thin cats are generally not prone to pancreatitis so your concerns there may not be necessary. Cat metabolism requires higher levels of fat than you might expect. "The Old Broad" is correct. You need to take your cat to the vet for an exam, blood testing and x-rays to check for diseases that may be causing weight loss, i.e. kidney disease, hyperthyroidism, heart disease and inflammatory bowel disease. Most of the conditions that cause weight loss in cats can be treated to offer a better quality of life in the later years.
    Dr. T

  • Stephanie Hulett
    03/01/2012 09:33pm

    Homemade diet recipes for calorie restriction are virtually non-existent as a generic offering and rightfully so. Every dog dieter is different with regard to their calorie restriction and supplementation needs. You need to search the internet for individuals that formulate homemade diets and have them work with your vet to formulate an appropriate recipe. Unfortunately all the human diet companies make counting calories seem easy. It is for humans because all of us have about the same nutrient requirements. Because the size, body type, and breed differences in dogs there is no generic weight loss solution for homemade diets. Also all pre-diet lab work and physical exams should be completed before contacting a homemade diet formulator. Most of these individuals require lab test before formulating any recipes, whether for dieting or special medical conditions. Your vet may already work with such an individual. Good luck.
    Dr. T

  • 03/08/2012 11:53pm

    From my wzper5ience . it has proven out thsat as long as a good quality dry food is fed.
    it seems that offering it "free chice"wil help dogd gfet to a good wseight.
    it seems in my experience thjat many dogsIF put on a restricted diet i.e. fed once or twice a day. will gobble up all he offered food quickjly. where as if the dog learns that any time it gets hungry it can go get a bite or two of food.
    case in point my brother had a pomerianian'cocoa that became seriously overweight being fed limited amounts of food at aet times of the day. once cocoa was started on adiet of high ptotein dog food "free choice " she quickly lost back to a we4ight level that her vet was very happy with.Cocoa even became so that if my brother offered her the same dogfood that caused herbecoming overweight. she would take a bite or two then go lay down or do something else for a wshile
    Most dogs do not ovedreat unless they are hungry. it seems that when they are hungry is when they will eat eceryting as fast as possible - overeating in the prodess
    this is sanalogous to people going grocery shopping when hungry and therefor buying more food than they know will be used in the next week or so.. that is why it is recpmmende that you eat something before going grocry shopping

  • The Old Broad
    03/02/2012 03:26am

    There is no universal vitamin supplement for dieting animals. As a matter of fact all pet vitamin formulations are completely inadequate for dieting pets. If they are on a veterinary weight loss formulation or a special formulated homemade diet supplements are not necessary. If you are dieting your pet on regular food and wanting a supplement you are missing my point. Dieting a pet is not a do-it-yourself project. Consult your vet, get on a weight loss diet and supplement according to the needs of the diet.
    Dr. T

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