Coffee makes you move more but sleep less, new study finds

A rigorous new study that examined the health effects of coffee consumption found good news and bad news for coffee lovers.

The research showed that coffee has striking effects on physical activity levels, causing people to move more, taking, on average, 1,000 extra steps a day — a significant boost in activity that might help explain why coffee consumption has long been linked to better health.

But the study, published in the New England Journal of Medicine, did find some downsides to a daily cuppa. It showed that people lost about 36 minutes of nightly sleep on days when they drank coffee — and the more coffee they drank, the less they slept.

The research also looked at coffee’s effect on heart palpitations, a relatively common experience for healthy coffee drinkers. The study found that in healthy men and women, coffee did not cause a common type of palpitation known as premature atrial contractions, even though some health authorities have warned that this could be a side effect of drinking coffee.

But coffee consumption can lead to an increase in another type of heart palpitation, known as premature ventricular contractions. These extra or irregular heartbeats are fairly common and benign. Almost everyone experiences them on occasion, and while they can be unnerving, most experts say they’re not usually a cause for concern in healthy people.

The findings suggest that the health effects of coffee are complex. While coffee is beneficial for many people and can lower the risk of chronic diseases and perhaps even extend your life span, it can also disrupt your sleep and may cause some heart palpitations.

“The reality is that coffee is not all good or all bad — it has different effects,” said Gregory M. Marcus, an author of the study and a professor of medicine in the division of cardiology at the University of California at San Francisco. “In general, this study suggests that coffee consumption is almost certainly generally safe. But people should recognize that there are these real and measurable physiological effects that could — depending on the individual and their goals of care — be harmful or helpful.”

Coffee is among the world’s most commonly consumed beverages, and decades of research suggest that it has mostly beneficial effects. Many observational studies show that coffee drinkers live longer and have lower rates of diabetes, cancer, liver disease, depression and other chronic conditions. But much of the data comes from large epidemiological studies, which show only correlations, not cause and effect. They also rely on self-reported data, which is not always reliable.

At the same time, the research on coffee and cardiovascular health has been somewhat conflicting. Early studies indicated that coffee might be detrimental to the heart because it spikes blood pressure, heart rate and adrenaline, and increases cholesterol levels.

More recent studies have found that drinking several cups of coffee daily — including decaffeinated coffee — could actually lower the risk of dying from heart disease or a stroke, which some experts attribute to the large amounts of antioxidants and other anti-inflammatory compounds in coffee.

Despite a lack of strong evidence, health authorities have often warned people with heart conditions, particularly those with heart rhythm disorders such as atrial fibrillation, to avoid coffee and other caffeinated beverages out of concern that they might trigger palpitations.

Source: Washington Post

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