When you drink your coffee matters
I’m a cyclist and coffee and cycling go hand in hand. I’m sure it’s true for most sports now that people use an espresso as a pick me up before doing a run or swim and then there’s the coffee with fellow athletes after a workout. There seems to be a long running debate about whether coffee is good or bad for you. How much of that is media and the crazy world of so called health influencers who knows. The science seems to suggest that a small amount of coffee could be good for us, with its polyphenols helping our gut microbiome. But what about when we drink our coffee? It’s common sense that drinking coffee before bed isn’t going to do any favours for a good nights sleep, but are there wider health implications?
A research team led by the Harvard T.H. Chan School of Public Health, wanted to test an hypothesis that distinct patterns of coffee drinking timing exist in the population and that these patterns are associated with mortality risk. Specifically, they aimed to explore whether drinking coffee in the morning is linked to lower mortality risk compared to drinking coffee later in the day.
The research team conducted the study by including 40,725 adults from the National Health and Nutrition Examination Survey (NHANES) who had complete dietary data. Additionally, 1,463 adults from the Women’s and Men’s Lifestyle Validation Study (WLVS and MLVS) were included, making the overall sample size substantial for the analysis. They utilised clustering analysis to identify distinct patterns of coffee drinking timing among participants.
The study involved a median follow-up period of 9.8 years, during which they recorded mortality events, including all-cause deaths and deaths due to cardiovascular disease (CVD) and cancer. The researchers adjusted for various confounding factors, such as age, sex, race, family income, education levels, and health conditions, to assess the association between coffee drinking timing and mortality risk.
Findings
The main findings of the study indicated that coffee drinking timing was significantly associated with all-cause mortality risk and cardiovascular disease (CVD)-specific mortality risk. Specifically, the researchers found that:
Two distinct patterns of coffee drinking timing were identified: a morning-type pattern (36% of participants) and an all-day-type pattern (14% of participants).
The morning-type pattern was associated with lower risks of all-cause mortality (hazard ratio: 0.84) and CVD-specific mortality (hazard ratio: 0.69) compared to non-coffee drinkers.
Higher amounts of coffee intake were linked to a lower risk of all-cause mortality, but this association was significant only in participants with the morning-type pattern, not in those with the all-day-type pattern , .
So if you want to reap the maximum benefits from your coffee, this research suggests that drinking coffee in the morning may be more beneficial for mortality risk than consuming it later in the day.
Why might this be the case?
The research suggests potential mechanisms that could explain why coffee drinking in the morning may be more beneficial. One proposed reason is that consuming coffee in the afternoon or evening might disrupt circadian rhythms. The study references a clinical trial indicating that heavy coffee consumption later in the day was associated with a significant decrease in peak melatonin production, a hormone crucial for regulating circadian rhythms. Low levels of melatonin have been linked to higher oxidative stress, elevated blood pressure, and increased cardiovascular disease risk.
The belief is that the timing of coffee consumption may play a role in maintaining healthy circadian rhythms, which could, in turn, influence overall health and mortality risk.