Effects of Intermittent Fasting on Anxiety and the Functional Connectivity of the Amygdala in Healthy Adults

This study assessed the effect of intermittent fasting on anxiety, depression, and connectivity of the amygdala by functional magnetic resonance imaging in healthy adults. The findings could provide insights into IF as a potential non-pharmacological intervention for anxiety, offering clinical significance as a cost-effective and accessible alternative or adjunct therapy.

Twenty-six healthy adults followed a time-restricted eating regimen for 50 days, fasting for 18 hours daily. Assessments were conducted at baseline, during fasting (days 10, 30, and 50), and after fasting (days 20 and ~60). Measurements included body mass index (BMI), metabolic parameters, Self-Rating Anxiety Scale (SAS), Self-Rating Depression Scale (SDS), and resting-state functional magnetic resonance imaging (fMRI) connectivity of the amygdala.

The BMI, glucose and insulin concentrations, insulin resistance, and anxiety scores significantly decreased during and after fasting compared to the baseline measurements (all p < 0.05), lasting for two months. Furthermore, we used the bilateral laterobasal amygdala as seed regions, which are responsible for emotional regulation and anxiety-like behaviours; we found changes in resting-state connectivity with the postcentral gyrus on fasting days 30 and 50.

IF reduces anxiety by modulating amygdala functional connectivity and enhancing brain plasticity, suggesting its potential as a therapeutic approach for anxiety and related emotional disorders. The findings underscore IF's promise as an alternative or adjuvant intervention in psychiatric care.

The study was registered at Clinicaltrials.gov (https://www.chictr.org.cn/showproj.html?proj=136213), registration number: ChiCTR2100052473.