For an 80-kg adult, a safe, sustainable pace is often ~0.5–1% of body weight per week—about 1.6–3.2 kg over 4 weeks. IF can help you reach that range, but success depends on food quality/portions, activity, and sleep. Large early scale drops may reflect water/glycogen rather than pure fat loss. Best practice: a moderate daily deficit (roughly 300–500 kcal), adequate protein, 2–3 resistance sessions weekly, more daily steps, and good sleep hygiene. If 16:8 triggers overeating, 14:10 may be more effective. With medical conditions or medications, personalize the plan with a clinician.