Intermittent Fasting Terms Explained
New to fasting or want to deepen your understanding? Browse our glossary of key terms, from autophagy to water fasting, each explained with scientific context and practical guidance.
16:8 Fasting
The most popular intermittent fasting method where you fast for 16 hours and eat within an 8-hour window each day.
Alternate Day Fasting
A fasting protocol that alternates between regular eating days and fasting or very-low-calorie days throughout the week.
Autophagy
The body's natural cellular recycling process where damaged or dysfunctional cell components are broken down and reused for energy or repair.
Circadian Rhythm Fasting
A fasting approach that aligns your eating window with your body's natural circadian clock, typically eating earlier in the day when metabolism is most active.
Eating Window
The designated period of time during which you consume all your daily calories and nutrients during intermittent fasting.
Extended Fasting
Any fast lasting longer than 24 hours, typically ranging from 36 hours to several days, that triggers deeper metabolic and cellular changes.
Fasting Window
The period of time during which you abstain from caloric intake, allowing your body to shift from fed-state metabolism to fasted-state fat burning.
Fat-Adapted
A metabolic state where your body has become efficient at using stored fat as its primary fuel source rather than relying on glucose from food.
Insulin Resistance
A condition where cells become less responsive to insulin, requiring the pancreas to produce more insulin to manage blood sugar levels.
Intermittent Fasting
An eating pattern that cycles between periods of fasting and eating, focusing on when you eat rather than what you eat.
Ketosis
A metabolic state where your body shifts from burning glucose to burning stored fat for fuel, producing ketone bodies as an alternative energy source.
OMAD (One Meal a Day)
An extreme form of intermittent fasting where you consume all daily calories in a single meal within a one-hour eating window.
Refeeding
The process of carefully reintroducing food after an extended fast to avoid digestive distress and the potentially dangerous refeeding syndrome.
Water Fasting
A type of fast where you consume only water for a set period, abstaining from all food and other beverages to maximize metabolic and cellular benefits.