16:8 Intermittent Fasting for Beginners
16:8 intermittent fasting means restricting all your eating to an 8-hour window each day and fasting for the remaining 16 hours — for example, eating between noon and 8pm. It's the most popular fasting pattern because it's simple, sustainable, and pairs naturally with keto to deepen fat-burning.
How to start 16:8
Pick an 8-hour eating window that fits your life — noon to 8pm suits most people because it simply means skipping breakfast. Drink water, black coffee or plain tea during the fasting hours.
If 16 hours feels like a lot at first, start with 14:10 and extend the fast by 30 minutes every few days until you reach 16:8 comfortably.
What to expect in the first week
Early hunger usually peaks around your old breakfast time and passes within 20 minutes. Mild headaches or low energy can occur as your body adapts — staying hydrated and keeping electrolytes up helps.
By the end of the first week most people find the window feels natural and appetite settles, because stable insulin levels reduce the blood-sugar swings that drive cravings.
Why 16:8 and keto work together
If you're already keto-adapted, you start each fast with low glycogen, so you reach the fat-burning and ketosis stages faster. Keto's appetite-suppressing effect also makes the fasting window easier to hold.
Keto Club's fasting timer tracks your window and shows which stage you've reached — fed, fat-burning, ketosis or autophagy — and adapts the suggested window to your current keto phase.
Frequently asked
Can I drink coffee while fasting?
Yes. Black coffee, plain tea and water are fine during the fasting window and won't break your fast. Avoid adding sugar, milk or cream, which contain calories and carbs.
Will 16:8 fasting break ketosis?
No — fasting deepens ketosis rather than breaking it. As long as your eating window stays low-carb, 16:8 supports and accelerates fat-burning.