Fasting & Glucose
topic
Fasting — including intermittent fasting protocols (16:8 time-restricted eating, 5:2 caloric restriction, alternate day fasting) and extended fasting — improves glycemic health through multiple mechanisms: reduction of insulin secretion during the fasting period allowing insulin sensitivity to restore, reduction of hepatic glucose production, activation of AMPK (the cellular energy sensor that improves insulin sensitivity), and promotion of cellular autophagy (the self-cleaning process that removes damaged cellular components including dysfunctional insulin receptors).
Role
Fasting for glycemic health is one of the most evidence-supported and most misapplied nutritional strategies — effective when implemented as genuine food abstinence during fasting periods and undermined when 'fasting' is used as justification for larger compensatory meals during eating windows that negate the insulin sensitivity benefits. The majority of people who have tried intermittent fasting have either implemented it as caloric restriction (which works but is not mechanistically distinct from standard caloric restriction) or experienced the hormonal adaptations that increase hunger during fasting periods without developing the metabolic flexibility that makes fasting genuinely therapeutic.