18:6 Intermittent Fasting vs One Meal A Day (OMAD) Fasting
18:6 Intermittent Fasting and One Meal A Day (OMAD) Fasting are both effective fasting protocols. 18:6 Intermittent Fasting involves a 18 hours fasting · 6 hour eating window; One Meal A Day (OMAD) Fasting involves a 23 hours fasting · 1 hour eating window. The right choice depends on your goals, experience, and lifestyle.
18:6 Intermittent Fasting
Advanced18 hours fasting · 6 hour eating window
18:6 intermittent fasting is a daily 18-hour fast with a 6-hour eating window — a meaningful step beyond 16:8 that deepens fat-burning, autophagy, and insulin reduction. It's typically reached naturally as the body adapts, and is best for experienced fasters.
Read full guideOne Meal A Day (OMAD) Fasting
Advanced23 hours fasting · 1 hour eating window
OMAD — One Meal A Day — is a 23:1 fasting protocol: one substantial, nutrient-dense meal per day. It maximizes daily autophagy and ketosis but carries significant risks of under-eating and nutrient deficiency, and requires careful meal construction.
Read full guide| Category | 18:6 Intermittent Fasting | One Meal A Day (OMAD) Fasting |
|---|---|---|
| Weight loss | ||
| Autophagy | ||
| Sustainability | ||
| For beginners | ||
| Metabolic health | Tie | Tie |
The bottom line
18:6 Intermittent Fasting and One Meal A Day (OMAD) Fasting are both effective fasting protocols. 18:6 Intermittent Fasting involves a 18 hours fasting · 6 hour eating window; One Meal A Day (OMAD) Fasting involves a 23 hours fasting · 1 hour eating window. The right choice depends on your goals, experience, and lifestyle. If you're new to fasting, start with the gentler protocol and build up. If your goal is deeper cellular benefits like autophagy, the longer fast wins. The best protocol is the one you can sustain.
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FaithFast offers education and encouragement, not medical advice. Consult a qualified healthcare provider before beginning any fasting protocol, especially if you are pregnant, breastfeeding, managing a medical condition, or taking medication.