Fasting Guides / Getting Started
16:8 vs 18:6 vs OMAD — Which Should You Do?
A breakdown of the three most common fasting windows, their trade-offs, and how to choose the right one for your lifestyle.
16:8 — The Starting Point
A 16-hour fast with an 8-hour eating window (e.g., noon to 8pm) is the most widely used approach and a great entry point. Most people are asleep for 8 of those 16 hours, which makes it surprisingly manageable. The eating window is generous enough to have two full meals and a snack. Hunger adapts within 1–2 weeks for most people.
18:6 — The Sweet Spot for Many
Narrowing to an 18-hour fast with a 6-hour eating window (e.g., 1pm to 7pm) increases the metabolic benefits without being extreme. Autophagy becomes more pronounced. Many people who have done 16:8 for a few months find 18:6 to be a natural next step that does not feel dramatically harder.
20:4 — Serious Compression
A 20-hour fast with a 4-hour eating window is sometimes called the Warrior Diet. It requires eating two smaller meals — or one large and one small — in a tight window. This works well for some people, but the short window makes it harder to meet protein needs and can lead to digestive discomfort if you try to eat too much at once.
OMAD — One Meal a Day
Eating all your daily calories in a single 1-hour window is the strictest common approach. Some people thrive on it — others find it unsustainable or physically uncomfortable. If you try OMAD, make sure that one meal is nutrient-dense. OMAD is not appropriate for everyone, particularly those with higher protein needs or a history of disordered eating.
How to Choose
Start with 16:8 for at least 3–4 weeks before extending. Let your hunger patterns and energy levels guide you. If 16:8 feels effortless after a month, try 18:6. Longer windows are not inherently better — consistency matters more than duration. A 16:8 you do every day beats an OMAD you abandon after two weeks.