Cut the Fat But Support the Cat

Dr. Caitlin Grant demonstrates a gap in essential nutrient intake when cats eat fewer calories for weight loss

When treating and preventing obesity in our companion animals, it is not uncommon for caregivers and members of the healthcare team to question: How low is too low when restricting calories for weight loss? Are our cats meeting their nutrient requirements during weight loss?

Entitled, Dietary intake of amino acids and vitamins compared to NRC requirements in obese cats undergoing energy restriction for weight loss, Dr. Caitlin Grant explored what nutritional gaps are present when feeding cats a restricted amount of food. 

One may consider that the treatment of obesity is a simple matter of adjusting the proportion of calories in compared to calories out. If the food amount is reduced, the body should burn fat! It sounds so simple! The challenge is, even when purpose formulated weight loss food is fed, a cat’s unique genetic make-up and individual metabolic rate may require an even lower feeding amount to create a negative caloric balance and induce weight loss. If food amount is reduced, there will then be a decrease in intake of essential nutrients. The question then becomes, how far can we restrict cats while still meeting nutrient intake requirements? 

To explore this question, Dr. Grant investigated nutrient intake in a group of cats fed a veterinary therapeutic weight loss diet. Cats were divided into an obese and lean group, based on body condition score, and were initially fed to maintain body weight. The obese cats then started a period of caloric restriction to induce weight loss.  

Although intake of the majority of essential nutrients met National Research Council (NRC) requirements, restriction led to an intake of choline and arginine below the NRC recommended allowance (RA) and even below NRC minimum requirement (MR). 

Cats in the study did not demonstrate signs of nutrient deficiency and remained healthy for the duration of the study, however there is a need to continue to investigate this topic and to specifically identify what the implications of this restriction may be for our feline weight loss patients. Moreover, future research should also focus on investigating what could be provided in the diet to better support cats during weight loss.  

Congratulations to Dr. Caitlin Grant for her recent publication in BMC Veterinary Research! 

Written by Shoshana Verton-Shaw, RVT, VTS (Nutrition)  

Edited by Dr. Caitlin Grant, BSc, DVM, DVSc. Res. ECVCN

Info-graphics created by Veronica Fursova, Work Study Student