Oriakhi Osareme Samuel, Human Physiology - Rivers State University, 2025

Intermittent fasting (IF) has gained increasing attention as a dietary strategy with potential benefits for weight regulation and metabolic health. This study investigated the effects of intermittent fasting on serum ghrelin and leptin concentrations in female Wistar rats. Twenty-four rats were divided into four groups: a control group fed ad libitum and three experimental groups subjected to fasting–feeding cycles of 6:18-hour, 12:12-hour, and 16:8-hour durations over a defined period. Body weight, relative organ weights, and serum levels of ghrelin and leptin were determined using standard biochemical assays. The results showed a significant reduction in body weight in all fasting groups compared with controls, with the most pronounced decrease observed in the 12:12 and 16:8-hour groups. Relative organ weights varied with fasting duration, suggesting enhanced metabolic activity during shorter fasting periods and metabolic conservation during longer fasts. Serum ghrelin levels increased significantly with longer fasting durations, indicating enhanced hunger signalling and energy mobilisation, while leptin levels decreased progressively, reflecting reduced adipose mass and energy intake. The inverse relationship between ghrelin and leptin supports their complementary roles in maintaining energy homeostasis during fasting. In conclusion, intermittent fasting induced duration-dependent hormonal and metabolic adaptations in female Wistar rats, promoting increased ghrelin secretion and decreased leptin production. These findings suggest that intermittent fasting may serve as a beneficial dietary intervention for improving energy balance and metabolic regulation.