72-Hour Fast Checklist

Who should not begin without medical guidance

Do not begin without guidance from a qualified clinician if you are under 18, pregnant or breastfeeding, have type 1 diabetes and use insulin, have a history of eating disorders, take medications affected by food timing, or have any condition where fasting may be unsafe for you.

Preparation checklist

• Confirm clinician guidance if any health condition, pregnancy, medications, or prior eating concerns apply
• Plan a low-demand window with rest and safe hydration access
• Stock plain water and label-checked fluids
• Identify who to contact if symptoms worsen
• Plan conservative refeeding food before you start
• Plan three low-demand days with overnight monitoring
• Identify medical contact before starting

Permitted non-caloric fluids

Check every label. If it contains calories, sweeteners that affect you, or ingredients you cannot verify, do not use it during the fast.

• Water — check labels on flavored or enhanced water
• Sparkling water without sweeteners
• Plain tea with no sweetener — verify no added calories on label
• Zero-calorie electrolyte drinks only if your clinician approves — read labels; avoid caloric sports drinks

Items and behaviors to avoid

• Any food or caloric intake
• Gum or mints with sugar
• Sweetened drinks, soda, or juice
• Creamer or sweetened coffee
• Caloric sports drinks
• Unnecessary stimulants beyond what you already tolerate