Morning-only coffee drinkers can take heart. Research shows consumption first thing is better for your health and mortality than all-day drinking.
People who drink coffee in the morning have a lower risk of dying from cardiovascular disease and a lower overall mortality risk compared to all-day coffee drinkers, according to the international research.
“Given the effects that caffeine has on our bodies, we wanted to see if the time of day when you drink coffee has any impact on heart health,” said United States lead researcher Professor Dr Lu Qi from Tuline University, New Orleans.
“Research so far suggests that drinking coffee doesn’t raise the risk of cardiovascular disease, and it seems to lower the risk of some chronic diseases, such as type 2 diabetes,” he said.
The study included 40,725 adults taking part in the US National Health and Nutrition Examination Survey (NHANES) between 1999 and 2018.
Study participants were asked about all food and drink consumption on at least one day, including whether they drank coffee, how much and when. It also included a sub-group of 1,463 people who were asked to complete a detailed food and drink diary for a full week. Researchers were then able to link this information with records of deaths and cause of death over a period of 9-10 years.
Results
Around 36% of people in the study were morning coffee drinkers (primarily drank coffee before midday), 16% of people drank coffee throughout the day (morning, afternoon and evening) and 48% were not coffee drinkers.
Compared with people who did not drink coffee, morning coffee drinkers were 16% less likely to die of any cause and 31% less likely to die of cardiovascular disease.
However, there was no reduction in risk for all-day coffee drinkers compared to non-coffee drinkers.
Morning coffee drinkers benefitted from the lower risks whether they were moderate drinkers (two to three cups) or heavy drinkers (more than three cups). Light morning drinkers (one cup or less) benefitted from a smaller decrease in risk.
This was the first study testing coffee drinking timing patterns and health outcomes, said Professor Qi.
“Our findings indicate that it’s not just whether you drink coffee or how much you drink, but the time of day when you drink coffee that’s important. We don’t typically give advice about timing in our dietary guidance, but perhaps we should be thinking about this in the future.”
“A possible explanation is that consuming coffee in the afternoon or evening may disrupt circadian rhythms and levels of hormones such as melatonin. This, in turn, leads to changes in cardiovascular risk factors such as inflammation and blood pressure.”
Further studies were needed to validate the findings in other populations, along with clinical trials to test the potential impact of changing the time of day when people drink coffee.
In an accompanying editorial published in the European Heart Journal, Professor Thomas F. Lüscher from Royal Brompton and Harefield Hospitals in London, United Kingdom affirmed the researchers’ hypothesis. “In the morning hours there is commonly a marked increase in sympathetic activity as we wake up and get out of bed, an effect that fades away during the day and reaches its lowest level during sleep.
“Thus, it is possible, as the authors point out, that coffee drinking in the afternoon or evening disrupts the circadian rhythm of sympathetic activity. Indeed, many all-day drinkers suffer from sleep disturbances. In this context, it is of interest that coffee seems to suppress melatonin, an important sleep-inducing mediator in the brain.
“Overall, we must accept the now substantial evidence that coffee drinking, particularly in the morning hours, is likely to be healthy. Thus, drink your coffee, but do so in the morning.”
The research is published in the European Heart Journal
‘Coffee drinking timing and mortality in US adults’, by X. Wang et al., European Heart Journal open access here
View the accompanying editorial ‘Start your day with a morning coffee!’ by T. F. Lüscher, European Heart Journal here
