Physiological effects of Intermittent fasting on glucose homeostasis and Insulin Sensitivity

Abstract

Aim: The aim of this study was to investigate the physiological effects of intermittent fasting
on glucose homeostasis and insulin sensitivity in healthy individuals, focusing on markers
such as fasting glucose, fasting insulin, HOMA-IR, and the Matsuda Index.
Materials and Methods: This Prospective study included 100 participants was conducted in
2018 in GMC Jammu, with equal distribution across gender and age groups (20–50 years), all
with a BMI in the normal range. Participants followed a 16:8 intermittent fasting regimen (16
hours of fasting with an 8-hour feeding window) while maintaining standardized dietary
intake and physical activity. Data were collected at baseline, midpoint (6 weeks), and
endpoint (12 weeks) on fasting glucose, fasting insulin, HOMA-IR, and the Matsuda Index.
OGTT tests were conducted at baseline and endpoint to assess glucose tolerance. Repeatedmeasures ANOVA was used to analyze changes over time, and regression analysis examined
correlations in glucose and insulin response.
Results: Over the study period, intermittent fasting significantly reduced fasting glucose
(95.2 mg/dL at baseline to 87.5 mg/dL at endpoint, p<0.001) and fasting insulin (10.5 μU/mL
to 8.6 μU/mL, p=0.001). HOMA-IR showed a marked decline, indicating improved insulin
sensitivity. OGTT results at the endpoint showed a significant reduction in glucose levels
across all time points (0, 30, 60, and 120 minutes), highlighting improved glucose tolerance.
The Matsuda Index increased significantly, from 3.2 at baseline to 4.5 at the endpoint
(p<0.001), confirming enhanced insulin sensitivity. Regression analysis demonstrated strong
correlations in glucose and insulin response changes over time, further supporting the
beneficial effects of intermittent fasting on metabolic health.
Conclusion: Intermittent fasting positively impacts glucose homeostasis and insulin
sensitivity, as evidenced by reductions in fasting glucose, fasting insulin, HOMA-IR, and
improved Matsuda Index scores. These findings suggest that intermittent fasting can be an
effective and practical approach to improve metabolic health in healthy adults, with potential
applications for preventing metabolic disorders.