Short answer: how often you should fast depends on your goals, health, and lifestyle. Common approaches range from daily time-restricted eating (for example, 14–16 hours fasting each day) to longer fasts done occasionally (24 hours weekly or 1–2 times per month). The best pattern is one you can sustain safely and that fits your health needs. Reasons to consider different frequencies

• Weight and metabolic health: Regular, moderate fasting windows (e.g., 12–16 hours daily) can support insulin sensitivity and weight management for many people.
• Autophagy and cellular repair: Some longer fasts (24 hours or more) or periodic fasting patterns are studied for cellular benefits, but they’re not necessary for everyone and carry higher risk of side effects if not supervised.
• Daily routine and energy: Shorter windows tend to be easier to maintain long-term and may minimize fatigue or headaches for many individuals.
• Medical conditions and medications: People with diabetes, low blood pressure, pregnant or breastfeeding individuals, or those on certain medications should approach fasting with medical guidance.

Practical starter recommendations (general, for healthy adults)

• Begin with a 12-hour fast each day (e.g., 7 pm to 7 am) and adjust based on how you feel.
• If tolerating well after a few weeks, try a 14–16 hour daily fasting window (e.g., 8 am–6 pm or noon–8 pm).
• For those seeking more structure, consider a 5:2-style pattern (eat normally 5 days, restrict calories on 2 non-consecutive days) or alternate-day fasting, but these require closer monitoring and may not be suitable for everyone.
• Shorter, regular fasts (12–16 hours) are generally safer and easier to sustain than frequent longer fasts.

Safety and caveats

• Hydration and electrolytes: Drink water and consider electrolytes during fasting, especially on longer fasts.
• Listen to your body: If you feel dizzy, faint, severely weak, or have other concerning symptoms, break the fast and seek guidance.
• Medical supervision: If you have diabetes, take glucose-lowering medications, are pregnant, or have a history of eating disorders, consult a healthcare professional before starting any fasting protocol.

If you share your goals (weight loss, blood sugar control, longevity, sport performance), current health conditions, and how you usually eat, a more tailored fasting plan can be suggested.