Heart healthy mornings: Drinking coffee early could lower CVD risks, new study finds

New research suggests drinking morning coffee lowers the risk of cardiovascular disease and mortality than drinking it all day.

Lead researcher Dr. Lu Qi from Tulane University, New Orleans, US, says this is the first study testing coffee drinking timing patterns and health outcomes. 

“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 advise about timing in our dietary guidance, but perhaps we should be thinking about this in the future.”

“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. Given caffeine’s effects on our bodies, we wanted to see if the time of day when you drink coffee has any impact on heart health,” he comments.

Published in the European Heart Journal, the study included 40,725 adults who participated in the US National Health and Nutrition Examination Survey (NHANES) between 1999 and 2018 and 1463 adults from the Women’s and Men’s Lifestyle Validation Study.

Study findings

According to the study, morning coffee drinkers had a 31% lower risk of dying from cardiovascular disease and a 16% lower risk of dying from any cause than those who did not drink coffee. 

Coffee drinking timing, intake amounts and mortality risk (Image credit: European Heart Journal).Coffee drinking timing, intake amounts and mortality risk (Image credit: European Heart Journal).Those who drank coffee in the morning, whether moderate (two to three cups) or heavy (more than three cups), benefited from the decreased risks. However, light morning drinkers (one cup or less) showed a smaller decrease in risk.

Qi explains: “This study doesn’t tell us why drinking coffee in the morning reduces the risk of death from cardiovascular disease. 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.”

However, when comparing all-day coffee drinkers to non-drinkers, the researchers found no risk decrease.

In the study, about 36% of participants drank coffee in the morning (mainly before noon), 16% drank coffee in the morning, afternoon and evening, and 48% did not.

Mounting evidence 

Researchers connected data from participant food and drink diaries to death records and cause of death data from nine to ten years ago.

In an accompanying editorial, professor Thomas F. Lüscher from Royal Brompton and Harefield Hospitals, London, UK, comments: “Why would time of the day matter? 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 [study] 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.”

“During a median follow-up of almost a decade, and after adjustment for caffeinated and decaffeinated coffee intake, the amounts of cups per day, sleep hours and other confounders, the morning-type, rather than the all-day-type pattern, was significantly associated with lower risks of all-cause mortality with a hazard ratio of 0.84 and cardiovascular mortality of even 0.69 as compared with non-coffee drinkers.”

Overall, Lüscher argues: “We must acknowledge growing evidence that coffee consumption, especially in the morning, is probably healthy. Thus, drink your coffee, but do so in the morning.”

However, Qi feels that more research is required to confirm the findings in different populations and that clinical trials are needed to study the possible effects of altering the time of day people drink coffee.

In other news, a study claiming to be the largest ever conducted on the human gut microbiome’s relationship with coffee consumption revealed a positive link to gut bacteria, particularly Lawsonibacter asaccharolyticus. This bacterium boosts the metabolization of quinic acid and trigonelline, which research links to a wide range of health benefits.

Other research on circadian nutrition highlights the transformative potential of meal timing in alleviating fatigue.