A diuretic effect has been observed when caffeine consumption exceeds how many milligrams per kilogram of body weight?

• A. 2 mg/kg
• B. 4 mg/kg
• C. 6 mg/kg
• D. 8 mg/kg

Answer: (B)

Caffeine’s diuretic effect depends on how much caffeine you’ve ingested relative to your body weight. This threshold is about 4 milligrams per kilogram, at which a noticeable increase in urine production tends to occur. So, for a 70 kg person, roughly 280 mg of caffeine would reach that level (about three cups of brewed coffee, depending on strength). Below this dose, many people don’t see a meaningful diuretic response. Individual factors like tolerance, hydration, and overall caffeine use can shift sensitivity, but 4 mg/kg is the commonly cited benchmark for when diuresis starts to appear.