研究表明，咖啡促进身体活动，减少睡眠，影响心跳

含咖啡因的咖啡可能会带来短期的好处和坏处, according to a study that monitored its health effects in real time.

研究人员在一项随机对照试验中对100名志愿者进行了为期两周的密切监测，发现喝咖啡的参与者每天的步数比不喝咖啡的参与者要多. 喝更多的咖啡与一种心律异常的发作次数减少有关.

但在喝咖啡的日子里，参与者发生另一种类型心跳异常的几率更高. They also slept less.

“这些研究结果强调了咖啡和健康之间的复杂关系，”研究作者Dr. Gregory Marcus, 加州大学心脏病学研究副主任兼房颤研究特聘教授, San Francisco.

"More physical activity, which appears to be prompted by coffee consumption, has numerous health benefits, such as reduced risks of Type 2 diabetes and several cancers, and is associated with greater longevity," Marcus said in a news release. "On the other hand, reduced sleep is associated with a variety of adverse psychiatric, neurologic and cardiovascular outcomes."

The research, 在同行评议的期刊上发表之前被认为是初步的, 是在上周末美国心脏协会的虚拟科学会议上提出的.

"Coffee is the most commonly consumed beverage in the world, yet its health effects remain uncertain," Marcus said. 大多数长期观察研究表明，喝咖啡有多种潜在的好处, 但他称这是“第一个调查实时情况的随机试验”, physiologic consequences of coffee consumption."

研究志愿者戴着连续记录监测器来跟踪心率和血糖水平. Wrist-worn devices tracked physical activity and sleep. The participants' average age was 38; 51% were women, and 48% were white.

Over two weeks, 他们被随机分配在不超过连续两天的线上电子游戏飞禽走兽里不喝咖啡或喝咖啡. 通过心脏监测器上的“线上电子游戏飞禽走兽戳按钮”实时跟踪咖啡和浓缩咖啡的消耗情况. 参与者每天完成问卷调查，详细说明他们喝了多少咖啡, and trips to coffee shops were recorded with geotracking.

Compared to days when participants did not drink coffee, coffee consumption was associated with more than 1,000 additional steps per day, 36 fewer minutes of sleep per night, 一种起源于下心室的异常心跳发作次数增加了54%, called premature ventricular contractions. 更频繁的下心室异常跳动增加了心力衰竭的风险，马库斯说.

每多喝一杯咖啡，每天多走近600步，每晚少睡18分钟. 而是由上心室引起的心律异常加快的发作, called supraventricular tachycardia, were 12% less frequent for each additional cup.

研究人员筛选了参与者的DNA，寻找可能影响咖啡因代谢的基因. 他们发现，当人们喝更多的咖啡时，携带与咖啡因代谢更快相关基因的人表现出更多源自心脏下腔的异常心跳. 喝咖啡的人代谢咖啡因的速度越慢，他们失去的睡眠就越多.

研究发现，喝咖啡对血糖水平没有影响.

研究人员观察了运动或睡眠的变化是否会影响咖啡对异常心律的影响. No such association was seen.

马库斯说，因为咖啡是随机分配给研究参与者的——通过反复评估每个参与者喝咖啡的天数和不喝咖啡的天数——可以推断出因果关系.

Find more news from Scientific Sessions.

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