Moderate coffee drinking is safe, and three to four cups a day may have some health benefits, according to a large review of previous studies, in the BMJ.

据对《英国医学期刊》以前的研究的大量回顾发现，适量的咖啡是安全的，每天三到四杯可能有一定的健康益处。

Too much coffee during pregnancy¹ could be harmful, the review confirmed.

该回顾证实，怀孕期间喝太多的咖啡会对身体有害。

Experts said people should not start drinking coffee for health reasons or to prevent disease.

专家称，人们不要为了身体健康或者预防疾病而开始尝试喝咖啡。

The University of Southampton researchers collected data on the impact of coffee on all aspects of the human body, taking into account more than 200 studies - most of which were observational.

南安普顿大学的研究人员收集了关于咖啡对人体各方面影响的数据，并采用了超过200份研究--其中大多数是观察性研究。

Was it the coffee? Compared with non-coffee drinkers, those who drank about three cups of coffee a day appeared to reduce their risk of getting heart problems or dying from them.

所以是咖啡的原因吗？与没有摄入咖啡的实验对象相比，一天喝三杯咖啡的人，患心脏疾病或因此丧命的风险更低。

The strongest benefits of coffee consumption were seen in reduced risks of liver disease, including cancer.

据观察，喝咖啡最大的益处就是能够降低患肝类疾病，其中包括肝癌的风险。

But Prof Paul Roderick, co-author of the study, from the faculty² of medicine at University of Southampton, said the review could not say if coffee intake³ had made the difference.

但是这项研究的合作者、来自南安普顿大学医学院的保罗·罗德里克教授表示，研究报告并不能确定是摄入的咖啡带来的这些差别。

"Factors such as age, whether people smoked or not and how much exercise they took could all have had an effect," he said.

他说道：“其他因素，如年纪、实验对象是否抽烟，他们的运动量多少，都可能造成影响。”

The NHS recommends pregnant women have no more than 200mg of caffeine a day - two mugs of instant coffee - because too much can increase the risk of miscarriage⁴.

英国国家医疗服务体系建议孕妇一天不要摄入超过200毫克的咖啡因，即两杯速溶咖啡，因为过量会增加流产的风险。

At present, the researchers said pinning down exactly how coffee might have a positive impact on health was "difficult".

研究人士表示，目前很难精准证明咖啡是如何为人体健康带来积极影响的。