Scientific Analysis of Intermittent Fasting (Bigu) in International Research: Health Management Strategies
Intermittent fasting, often referred to as “Bigu” in traditional Chinese practices, has gained global scientific attention as a health management strategy. Below is a synthesis of its methodologies, health benefits, and mechanisms based on international studies.
1. Types of Intermittent Fasting Regimens
a. Alternate-Day Fasting (ADF)
Protocol: Alternating between fasting days (0–25% energy intake) and ad libitum eating days.
Evidence: Studies show 3–7% weight loss, reduced body fat (3–5.5 kg), and improved lipid profiles (10–21% reduction in cholesterol, 14–42% in triglycerides) over 3–12 weeks . Modified ADF (e.g., 5:2 diet—two restricted days per week) also supports metabolic health without severe energy deprivation .
b. Time-Restricted Feeding (TRF)
Protocol: Restricting daily eating to an 8–10-hour window (e.g., 16-hour fast).
Evidence: Limited but promising data suggest TRF improves circadian rhythm alignment, gut microbiota diversity, and metabolic markers like glucose tolerance . Late-night eating disruptions are linked to obesity and diabetes, highlighting TRF’s preventive potential .
c. Whole-Day or Prolonged Fasting
Protocol: Extended fasting periods (24–72 hours), often integrated with religious practices (e.g., Ramadan).
Evidence: Ramadan fasting (12-hour daily fasting) improves insulin sensitivity and reduces inflammation, though outcomes vary based on dietary habits post-fast .
d. Religious and Cultural Fasting
Examples: Ramadan (Islamic fasting), Orthodox Christian fasting.
Health Impact: Observational studies note reduced cardiovascular risks and improved lipid profiles, though results depend on post-fast dietary choices .
2. Health Benefits Supported by Research
a. Weight and Body Composition
Intermittent fasting reduces body weight (3–9%) and visceral fat, particularly in overweight/obese populations. ADF and modified fasting show sustained fat loss without muscle depletion .
b. Metabolic Health
Glucose Regulation: Fasting lowers insulin levels, enhances insulin sensitivity, and stabilizes blood glucose, reducing type 2 diabetes risk .
Lipid Metabolism: Triglycerides and LDL cholesterol decrease by up to 50% and 20%, respectively, with ADF and whole-day fasting .
c. Anti-Inflammatory and Anti-Aging Effects
Fasting triggers autophagy (cellular repair) and reduces oxidative stress. Studies report lower inflammatory markers (e.g., TNF-α, IL-6) and increased adiponectin .
Ketogenesis during fasting provides neuroprotective benefits, potentially delaying neurodegenerative diseases .
d. Gut Microbiota and Circadian Rhythm
Fasting enriches beneficial gut bacteria, enhancing gut barrier function and reducing inflammation . Synchronizing eating with circadian rhythms (via TRF) optimizes metabolic processes and sleep quality .
3. Mechanisms Underlying Health Effects
Ketogenesis: Fasting shifts metabolism to ketone bodies, improving brain function and fat oxidation .
Hormonal Modulation: Growth hormone increases (promoting muscle preservation), while insulin decreases (facilitating fat breakdown) .
Cellular Stress Resistance: Fasting activates pathways like AMPK and sirtuins, enhancing mitochondrial efficiency and stress resilience .
4. Considerations and Recommendations
Population-Specific Adaptations: Fasting may not suit pregnant women, adolescents, or individuals with eating disorders. Customized protocols are essential .
Combination with Exercise: Synergistic effects of fasting and exercise improve body composition and cardiovascular health .
Long-Term Adherence: Gradual implementation (e.g., starting with 12-hour fasts) enhances compliance and minimizes side effects like fatigue .
5. Gaps and Future Research
Long-Term Efficacy: Most studies are short-term (≤24 weeks); longitudinal data are needed .
Comparative Studies: Direct comparisons between fasting types (e.g., ADF vs. TRF) remain limited .
Cultural Context: Further exploration of traditional practices (e.g., Taoist Bigu) in modern scientific frameworks is warranted .
Conclusion
Intermittent fasting, as validated by international research, offers a versatile approach to improving metabolic health, weight management, and longevity. While methodologies vary, adherence to evidence-based protocols and individualized adjustments are key to maximizing benefits. Future studies should bridge traditional practices (e.g., Bigu) with contemporary science to refine global health strategies.
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