William R. Pritchard Veterinary Medical Teaching Hospital

Nutritional Management of Diabetes Mellitus

Nutritional Management of Diabetes Mellitus - Andrea J. Fascetti and Sean J. Delaney

The goal in treating your pet's diabetes mellitus is to keep your dog or cat happy and to provide them as stable of life as possible. Nutrition is an integral part of the management of any diabetic patient. This is because diabetes mellitus is caused by an absence or a reduction in the activity of insulin, the substance that moves sugar into the body's cells for use as an energy source.

In order to reach our overall objective of maintaining your pet's quality of life, there are several important goals that we try to achieve with regard to nutritional management of the disease. These goals include; 1) maintenance of food intake to provide adequate calories, 2) maintenance of a healthy body weight and body condition, 3) weight loss if indicated and 4) the reduction or elimination of the clinical signs of diabetes, while at the same time avoiding the common complications of the disease.

Controlling blood glucose (or sugar) concentrations within a healthy range is important in achieving these goals. This can be done using medication (usually insulin or an oral drug), nutrition, or a combination of both. The best approach varies from patient to patient, and it may take some time to determine which approach meets your pet's unique needs.

Prescription Diets
In some cases your veterinarian may choose to change your pet to a special prescription diet to help manage their diabetes. Fiber-enhanced foods have been used successfully in the management of both canine and feline patients with diabetes mellitus for years. Fiber is proposed to promote a slower digestion and absorption of dietary carbohydrates (the major provider of blood glucose or sugar in the food), reducing peaks in blood sugar after meals. Some types of fibers are also believed to form gels in aqueous solutions (such as found within the gastrointestinal tract), thereby binding glucose and water and preventing their transfer to the absorptive surface of the intestine. This may also aid in reducing fluctuations in blood sugar concentrations following a meal. The overall effect is the maintenance of blood glucose concentrations within a more healthy range and a reduction in the side effects associated with poor blood sugar control.

There are several studies that support the feeding of low carbohydrate diets for the management of cats with diabetes mellitus. These foods contain higher concentrations of both protein and fat in order to reduce the amount of carbohydrate in the diet. Cats are carnivores and their systems are designed to digest and metabolize foods high in protein. Due to the limited amount of carbohydrate in these diets, the consumption of such foods may reduce the elevations in blood sugar concentrations following a meal, or reduce the amount of insulin needed for the body's cells to be able to use circulating glucose. If they need additional sugar beyond what is supplied in these low carbohydrate foods, the cat can take the protein and fat from the diet and turn it into glucose to meet their body's needs. The use of low carbohydrate diets for the management of canine diabetes has not been investigated.

Obesity
Obesity has been identified as a risk factor for the development of diabetes mellitus in cats, and in some cases, weight loss can lead to the resolution of the disease. In both dogs and cats with diabetes mellitus, the presence of obesity can make it more difficult to control blood sugar concentrations within a healthy range, predisposing them to additional complications. For these reasons, diabetic dogs and cats that are overweight should be started on a weight loss program once their diabetes is stabilized.

There are many different approaches with regard to diets designed for weight loss. Fiber-enhanced foods and low carbohydrate diets, which are often used in the nutritional management of diabetes mellitus, can also be used for weight loss. Fiber-enchanced foods may contribute to satiety (a feeling of fullness) and this characteristic can be a beneficial to a successful weight loss program. Furthermore, fiber reduces the caloric density of a diet, permitting a larger volume of food to be fed to the animal. A diet with reduced carbohydrate content may alter the animal's metabolism to utilize more fat for energy and lead to weight loss. Although the use of low carbohydrate diets for the management of diabetes mellitus is currently limited to cats, this type of food has been used for weight loss in both dogs and cats. It is interesting to note that in studies examining the efficacy of both fiber-enhanced and low carbohydrate diets for the management of diabetes mellitus, overweight animals that responded positively to both types of diets frequently lost weight as well. This certainly supports weight loss for the reversal or improved control of diabetes mellitus in both dogs and cats. For additional information about programs and foods designed for weight loss, please refer to the client handout on obesity.

If your animal is placed on a weight reduction plan, it is imperative that you regularly re-check with your veterinarian while your animal is on the program. As your animal losses weight, it will often need less insulin or other medication to maintain its blood sugar levels within a healthy range. Failure to see your veterinarian and have the medication adjusted appropriately can lead to an episode of hypoglycemia, which in some cases can be fatal.

Pancreatitis
Pancreatitis is a common complication of diabetes mellitus in dogs, but it is also recognized in feline patients. Pancreatitis may or may not be accompanied by a concurrent elevation in blood lipid levels, often referred to as hyperlipidemia. In cases where only blood triglycerides are increased, it is called hypertriglyceridemia. In many, if not all cases, a dietary change is necessary to prevent recurrence of the pancreatitis, and if indicated, reduce blood lipid concentrations. Usually this is accomplished by reducing, or in some cases severely restricting fat in your pet's diet. In many cases, in order to prevent future episodes of pancreatitis or to reduce blood lipid levels, your pet will need to remain on a low fat diet for the rest of its life. In order to prescribe a diet with lower fat levels than your pet is currently eating, your veterinarian will need a thorough and extensive diet history on your animal. This information will be vital to assist them in selecting your pet's new diet, so it is important that your report be as accurate as possible.

Nutritional Management at Home
In some cases, your veterinarian may chose to place your pet on a veterinary prescription diet to aid with the management of the diabetes mellitus, however in some cases they may chose to keep your pet on its regular diet. There are many factors that influence the decision whether to change diets and the appropriate time to do so. Every patient is different and has unique needs, and your veterinarian will advise you with regard to what they think the best choice is for your animal. They will also provide detailed instructions regarding how to feed the diet, and when to administer insulin or oral hypoglycemic drugs in relation to meals if indicated.

However, no diet can be of benefit unless your animal eats it. Some medications, especially insulin, can be harmful, if not deadly when given to an animal that is not eating. It is imperative that you monitor your pet's food consumption daily. Animals with diabetes mellitus may reduce their food intake or stop eating for many reasons. Some may be as simple as they don't like the diet, or more serious such as the development of a concurrent disease process. If you notice a reduction or cessation in your animal's food intake, contact your veterinarian immediately for further guidance and advice.

No part may be reproduced without the written permission of the authors. Version 4-04.