一天喝多少咖啡算适量

发表于新英格兰医学(世界顶级医学期刊)上一项基于500万人年的研究表明，大于一杯以上的日均摄入量中观察到了总死亡率下降的现象。且以日均4~5杯下降最明显，男性下降约12%，女性下降约16%。
附result的部分简介
RESULTS: During 5,148,760 person-years of follow-up between 1995 and 2008, a total of 33,731 men and 18,784 women died. In age-adjusted models, the risk of death was increased among coffee drinkers. However, coffee drinkers were also more likely to smoke, and, after adjustment for tobacco-smoking status and other potential confounders, there was a significant inverse association between coffee consumption and mortality. Adjusted hazard ratios for death among men who drank coffee as compared with those who did not were as follows: 0.99 (95% confidence interval [CI], 0.95 to 1.04) for drinking less than 1 cup per day, 0.94 (95% CI, 0.90 to 0.99) for 1 cup, 0.90 (95% CI, 0.86 to 0.93) for 2 or 3 cups, 0.88 (95% CI, 0.84 to 0.93) for 4 or 5 cups, and 0.90 (95% CI, 0.85 to 0.96) for 6 or more cups of coffee per day (P<0.001 for trend);

人每日咖啡因摄入上限为400毫克，一小袋(15克)速溶咖啡咖啡因含量约为50毫克。再加上速溶咖啡中糖和植脂末及添加剂的影响，每天喝咖啡不宜超过两杯。

每天根据个人身体健康壮况而定，十到二十克最好。

什么东西适量就行，过多了起反作用，自己的身体自己注意

不超过30克