Immunomodulatory Effects of Fasting in Healthy Adults

Eligibility Criteria

• * Age: 20-40 years, to constitute a young study population
• * Gender: male subjects, to control for gender differences
• * BMI: 19-27 kg/m2 to constitute a normal/healthy weight population
• * Weight: 120 lbs or more
• * Fasting glucose: 70-100 mg/dL, to ensure that fasting can be tolerated without inducing dangerously low levels of blood glucose
• * Subjects must be willing to undergo a period of 36 hours of water-only fasting
• * Subjects must be willing to collect samples of each bowel movement produced throughout the entire study period for microbiome analysis
• * Subjects must be willing to collect blood pricks for blood glucose levels using a Contour Next One Blood Glucose Testing Kit during the fasting stage of the study protocol.
• * Current smoking
• * Anemia
• * Pregnancy or current breastfeeding
• * Chronic diseases including diabetes mellitus, thyroid disease, metabolic syndrome, cancer, or previous cardiovascular events
• * Gastrointestinal diseases including irritable bowel syndrome, Crohn's disease, ulcerative colitis, celiac disease
• * Consumption of \>1 alcoholic drink/day
• * Extreme dietary or exercise patterns
• * Recent weight fluctuations (greater than 10% in the last six months)
• * Regular use of over-the-counter allergy or pain medications (\>1/week)
• * Taking prescription lipid medications (e.g. statins) or other supplements known to alter lipoprotein metabolism such as isoflavones
• * Use of hormonal birth control including oral contraception pills, hormonal IUDs or rings, or hormonal birth control patches