Effect of feeding a weight loss food beyond a caloric restriction period on body composition and resistance to weight gain in cats.

OBJECTIVE: To determine the effect of feeding a food with coconut oil and supplemental L-carnitine, lysine, leucine, and fiber on weight loss and maintenance in cats. DESIGN: Prospective clinical study. ANIMALS: 50 overweight cats. PROCEDURES: The study consisted of 2 trials. During trial 1, 30 cats were allocated to 3 groups (10 cats/group) to be fed a dry maintenance cat food to maintain body weight (group 1) or a dry test food at the same amount on a mass (group 2) or energy (group 3) basis as group 1. During trial 2, each of 20 cats was fed the test food and caloric intake was adjusted to maintain a weight loss rate of 1%/wk (weight loss phase). Next, each cat was fed the test food in an amount calculated to maintain the body weight achieved at the end of the weight loss phase (weight maintenance phase). Cats were weighed and underwent dual-energy x-ray absorptiometry monthly. Metabolomic data were determined before (baseline) and after each phase. RESULTS: During trial 1, cats in groups 2 and 3 lost significantly more weight than did those in group 1. During trial 2, cats lost a significant amount of body weight and fat mass but retained lean body mass during the weight loss phase and continued to lose body weight and fat mass but gained lean body mass during the weight maintenance phase. Evaluation of metabolomic data suggested that fat metabolism was improved from baseline for cats fed the test food. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that feeding overweight cats the test food caused weight loss and improvements in body condition during the weight maintenance phase, possibly because the food composition improved energy metabolism.