Evaluation of the Nutritional Profile and Obesogenic Potential of a Formulated High-Fat Diet

Abstract

High-fat diets (HFDs) are commonly used in nutritional research to model obesity and associated metabolic disorders. However, detailed profiling of their nutritional composition and physiological effects is essential for model validation. The present study developed standardized HFDs using locally available beef tallow as a cost-effective fat source and evaluated both the nutritional profile of these formulated diets and their efficacy in promoting obesity progression using male Wistar rat models. Fifteen (15) male Wistar rats were locally sourced and used for the study. They were grouped into three (3) of five (5) animals each. Group I served as the control and received standard rat chow (SRC) while groups II and IIIreceived SRC blended with 10% (HF-10) and 20% (HF-20) beef tallow respectively. The experiment lasted for ten (10) weeks during which all the animals were allowed access to feed and water ad libitum. Proximate analysis of the rat diets and faecal matter were determined using standard methods. Feed efficiency, nutrient digestibility, and morphometric parameters were determined using standard formula. Results from the study indicate that protein and fibre content of the rats’ feed was reduced with increased fat supplementation with the HF-20 rat showing the highest energy (4144.1 Kcal/kg) and 64.8% increase in feed efficiency compared to the SRC diet. Also, HF diets increased body weight (35%), Lee’s obesity index (18.5%), abdominal circumference (43.5%), absolute adipose tissue weight (776.43%) and adiposity index (529.2%) in a dose-dependent manner. The faecal proximate composition analysis showed a slight increase in ash and lipid excretion with an enhanced fat digestibility coefficient. Evidence from the present study shows that a high-fat diet containing 20% beef tallow (HF-20) effectively induced obesity and associated metabolic disturbances in male Wistar rats. The findings demonstrate a clear dose-response relationship between dietary fat content and the development of obesity-related phenotypes. These findings highlight the use of HFD in understanding the pathophysiology of obesity and metabolic disease, while also providing a practical animal obesity model for preclinical research.