Therapeutic diets: Food you can use (Proceedings)


Therapeutic diets: Food you can use (Proceedings)

Therapeutic diets represent another aspect of treatment of specific diseases in addition to conventional therapy. These diets are designed for one or more diseases and formulated to contain a nutrient composition that may be of benefit in treating these diseases. They are typically fixed-formulation diets and contain better quality ingredients; therefore, they tend to be more expensive. We will take individual diseases, use the 3-step process to identify the characteristics of a diet that might be desirable for managing that disease, and examine examples of commercially available diets.

The American College of Veterinary Nutrition, a specialty college of board-certified nutritionists that are also veterinarians, recommends a two-step process in making nutritional recommendations. The process is iterative in that it should be re-evaluated periodically and changes made as deemed necessary. The first step is ASSESSMENT. During this step, assess the ANIMAL, the DIET, and the FEEDING factors. ANIMAL FACTORS to be assessed include gathering historical information, performing physical examination, body condition scoring, and evaluating laboratory and imaging results if indicated. Gather information on any health or disease-related conditions, medications (including over-the-counter and nutraceuticals/supplements), reason for visit, and other household members. A thorough physical examination is performed and a body condition score assigned. There are 5- and 9- point body condition scoring systems; either can be used. Assigning a body condition score provides more information than body weight alone and takes into account muscle mass and tone.

DIETARY FACTORS include gathering information on dietary intake and inspection of the food, if needed. Take the dietary history from the person that actually feeds the pet(s) asking for type of food, amount fed, frequency of feeding, table food or treats, access to other food (garbage, outside, etc), supplements, and medications (including over-the-counter). If necessary, inspect a sample of the food or send a sample for analysis (i.e. Cornell Animal Health Diagnostic Center, Woodson Tenent Laboratories, EMSL Food and Consumer Products Testing Lab, etc). Pet foods can be purchased in a variety of forms – dry, canned, semi-moist, semi-dry, liquid, and frozen.

Reading the food label is also beneficial. The food label can be roughly divided into a principal display panel and an information panel. The PRINCIPAL DISPLAY PANEL contains information directed towards the consumer including the product name, species for which the food is intended, net weight of product, and descriptive words and/or pictures (e.g. "new and improved", picture of a famous cat, etc). The INFORMATION PANEL contains the important information including ingredient list, guaranteed analysis, feeding guidelines, contact information, and the nutritional adequacy statement. Although often maligned and not as complete as labels for human foods, there is useful information to be found. Ingredients are listed in descending order according to pre-processing weight and names are set by AAFCO (e.g. by-product, etc); this means that ingredients containing moisture that weigh more will be listed first. Unfortunately, this does not give information as to the quality or exact amount of each ingredient; also, different forms of the same type of ingredient are listed separately. Chemical sounding ingredients are typically vitamins, minerals, and preservatives. Feeding guidelines are provided that are suitable for most, but not all, dogs or cats that consume the diet. The manufacturer's or distributer's name and address is required and questions regarding the food should be directed to them; they should be able and willing to provide answers.

The guaranteed analysis provides information regarding the 4 major components of a pet food as percentages of the diet as fed including minimum amount of crude protein, minimum amount of crude fat, maximum amount of crude fiber, and maximum amount of moisture. "Crude" refers to the analytical procedure and does not refer to the quality of the ingredient. Because the guaranteed analysis is in percentage as fed, it is difficult to compare products that differ in composition (e.g. dry product versus canned product); therefore, comparing products on a "dry matter" basis or on a gram per 100kcal basis is preferred. A down-and-dirty rule-of-thumb for comparison is:

• For dry foods – add 10% to nutrient of interest AF
      o Ex. 21% protein AF = 21 + (21 × 0.1) = 21 + 2.1 = 23% protein DM

•For canned foods – multiply nutrient by 4
      o Ex. 5% protein AF = 5 × 4 = 20% protein DM