Week 1: 1-3 lbs lost (mostly water/glycogen). Weeks 2-4: steady 0.5-1 lb fat loss per week. Month 2-3: reduced hunger, better energy, improved blood sugar. 16:8 works by creating a natural calorie deficit — most people eat 20-30% fewer calories when restricted to an 8-hour eating window without consciously counting.
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📉 Calorie Deficit Calculator →🤖 Ask AI Coach →Week 1: 1-3 lbs lost from water and glycogen. Weeks 2-4: 0.5-1 lb fat loss per week if in a calorie deficit. Month 2-3: reduced hunger, improved energy, better blood sugar stability. Most people eat 20-30% fewer calories naturally when restricting their eating window.
16:8 means fasting for 16 hours and eating within an 8-hour window. Most popular windows: 12pm-8pm (skip breakfast), 10am-6pm (early lunch), or 8am-4pm. The specific hours matter less than consistency.
Yes. During the fasting window: water (unlimited), black coffee (no sugar, no cream), plain tea (no additives), and sparkling water are all fine. Avoid anything with calories including milk in coffee, even small amounts of cream, or diet sodas that may trigger insulin response in some people.
Weight loss depends on total calorie intake, not just timing. 16:8 works because most people naturally eat less when their eating window is restricted — an average reduction of 350-500 calories per day. This produces 0.5-1 lb fat loss per week for most people.
Yes. Multiple studies show 16:8 intermittent fasting preferentially reduces visceral belly fat (the dangerous internal fat) by 4-7% over 8-12 weeks. The extended fasting period increases fat oxidation and reduces insulin levels, both promoting visceral fat reduction.
Common mistakes: overeating during the eating window (negating the deficit), eating high-calorie foods thinking the timing makes calories irrelevant, not drinking enough water during the fast, breaking the fast with sugary foods causing blood sugar spikes, and starting with exercise during fasting before adapted.
Avoid 16:8 if: you have a history of eating disorders, you are pregnant or breastfeeding, you are a Type 1 diabetic on insulin, you are under 18, or you have a medical condition that requires regular eating. Always consult your doctor first.
For many people, yes — the restricted eating window naturally reduces calorie intake without counting. Studies show average spontaneous calorie reduction of 20-30% with 16:8 fasting. However, people who compensate by eating large high-calorie meals in the window do not lose weight.