大概是多少? 這取決於你身體的新陳代謝機能，正常情況下體重爲70kg的成年人飲用量每天小於500mg，建議是每天4-6杯咖啡300-400mg左右的攝入量。

　　How much is too much? It depends on how fast your body metabolises caffeine, but as a general rule: "A high dose of caffeine is 500mg per day, based on a 70kg adult, which works out at six to eight cups of instant coffee," says Karen Dickinson, of Body Acoustics Health and Sports Nutrition. "A moderate dose is 300 to 400mg per day; four to six cups."

　　那麼常見的飲品中，都含有多少的咖啡因呢?以下是每100毫升單位的咖啡因含量數據：

　　Here's how much caffeine (in mg per 100ml) is contained in some of your favourite beverages...

　　可可 Coca-Cola: 9.7 mg/100ml

　　速溶咖啡 Instant Coffee: 24.1 mg/100ml

　　濃縮咖啡 Espresso Coffee: 173.6 mg/100ml

　　手衝純咖啡(黑咖啡) Plunger Coffee: 45.4 mg/100ml

　　低咖啡因咖啡 Decaf (instant) Coffee: 1.1 mg/100ml

　　健怡可樂 Diet Coke: 12.7 mg/100ml

　　能量飲料Lift Plus: 14.5 mg/100ml

　　能量飲料 百事可樂 Pepsi Max: 19.4 mg/100ml

　　能量飲料 無糖百事可樂 Diet Pepsi: 10.1 mg/100ml

　　能量飲料 紅牛 Red Bull: 32 mg/100ml

　　能量飲料 紅牛能量飲料 Red Bull Energy Shot: 133.3 mg/100ml

　　茶 Tea (white): 6.3 mg/100ml

　　這個是澳洲品牌的能量飲料，還沒進入中國 V Pocket Rocket Energy Shot: 266.5 mg/100ml