Drinking coffee at the right time of day could hold the key to a longer, healthier life—discover how your morning brew may protect your heart and boost longevity!
Study: Coffee drinking timing and mortality in US adults. Image Credit: wk1003mike / Shutterstock
In a recent study published in the European Heart Journal, researchers in the United States investigated the associations between coffee drinking (particularly, the timing of coffee consumption) and mortality (all-cause or cause-specific). Their analyses of more than 42,000 adult US citizens from the National Health and Nutrition Examination Survey (NHANES) and the Women’s and Men’s Lifestyle Validation Study (WLVS and MLVS) revealed two distinct clusters – those that consumed coffee during the morning hours (morning type) and those that drank coffee throughout the day (all-day-type).
Study findings revealed that the morning-type cluster presented substantially lower cardiovascular disease (CVD)-specific and all-cause mortality than non-coffee drinkers or the all-day-type cluster participants, suggesting that moderate coffee consumption during the morning hours may help reduce mortality risk and extend lifespans in US populations. However, the study emphasizes that this is an observational finding and cannot confirm causation.
Background
Coffee brewed from roasted coffee plant beans is among the most popular drinks globally. Several prospective studies have investigated the health impacts of coffee consumption, with results suggesting that in moderation, coffee can reduce the risks of Type 2 Diabetes (T2D), cardiovascular diseases (CVDs), and all-cause mortality. These benefits prompted the United States (US) Dietary Guidelines (2015-2020) to include moderate coffee consumption in their recommendations for healthy diet items.
Unfortunately, caffeine (a stimulant found in coffee beans and, to lesser extents, tea) has been reported to be addictive, prompting studies to evaluate the effects of excessive coffee consumption (>3 cups/day). Tolerance to coffee and coffee intake, however, vary based on several factors, including genetics, behaviors (e.g., smoking), and additives (e.g., sweeteners), confounding the outcomes of these studies, most of which comprise limited sample sizes.
Recent research has increasingly highlighted the importance of circadian rhythms in regulating human metabolism and health outcomes. Studies indicate that the timing of food intake can significantly influence its impact on health. Despite coffee being commonly used to support wakefulness and prevent drowsiness (given its stimulatory effects), the impacts of coffee consumption across different times of day remain largely unexplored.
About the Study
The present study uses cluster analyses to identify patterns in coffee consumption of a large US population (n = 42,188) and subsequently investigate the associations between these patterns and mortality risk. Study participants were derived from the National Health and Nutrition Examination Survey (NHANES; n = 40,725), with an additional sample cohort – the Women’s and Men’s Lifestyle Validation Study (WLVS and MLVS; n = 1,463) – used for external validation. Participants with CVD, pregnant women, or those who had cancers at baseline were excluded from the analyses.
Study data was collected using 24-hour dietary recall questionnaires comprising timings, amounts, and types of beverages and food consumed in the previous midnight-to-midnight interval. Additionally, in-person physical examinations were conducted at baseline and throughout the 9.8-year-long follow-up period.
Statistical analyses included generalized linear models (for covariance estimations) and chi-square (χ2) for comparisons between variables of interest. Cluster analyses (hybrid approach) were used to identify patterns of coffee consumption. The researchers also adjusted for numerous confounding variables, such as smoking status, sleep patterns, dietary quality, and physical activity, to strengthen the reliability of their findings. Subsequently, hazard ratios (HRs; Cox proportional hazards models) were computed to evaluate the associations between identified clusters and their respective all-cause and cause-specific mortality rates.
Study Findings
Clustering analyses identified two distinct patterns of coffee consumption timings: morning (36% of participants; 4 a.m. to 11:59 a.m.) and all day (16%; morning, afternoon, and evening). Surprisingly, morning-type coffee drinkers consumed higher quantities of tea and caffeinated soda than their all-day counterparts (who primarily consumed coffee throughout the day).
Cox proportional hazards models revealed that morning-type coffee drinking reduced all-cause mortality events (HR = 0.84) and CVD-specific mortality (HR = 0.69) compared to non-coffee consumers. In contrast, all-day-type coffee drinking was statistically indistinguishable from no coffee consumption. Importantly, all-day-type coffee drinkers showed neither harm nor benefit in terms of mortality risk. These findings remained consistent even after adjusting for confounding variables (sex, age, sleep patterns, smoking status, etc.).
Notably, a positive correlation between the amount of daily coffee intake and mortality rate outcomes was observed for morning-type participants—higher coffee intake (>3 cups/day) improved mortality rate outcomes compared to lower coffee intake (1 cup/day)—with hazard ratios improving from 0.85 for the latter cohort to 0.79 for the former. Once again, no improvement in the quantity of coffee consumed could be established in mortality outcomes for all-day-type coffee consumers.
Conclusions
The present study is the first to elucidate the impacts of different coffee consumption timings on all-cause and cause (CVD)-specific mortality in a large US population. Study findings identified two main types of coffee drinkers – 1. morning-type and 2. all-day-type. The findings suggest that the timing of coffee consumption may play a crucial role in its health effects, potentially due to its interaction with circadian rhythms and anti-inflammatory mechanisms. The study highlights that restricting coffee consumption to the morning hours (4 a.m. to 11:59 a.m.) significantly reduces mortality rates across both all-cause and CVD-specific mortality. In contrast, all-day-type coffee consumers showed no such health benefits. These results underscore the need for further research to explore causative factors and confirm findings across diverse populations.
“Our findings highlight the importance of considering drinking timing in the association between the amounts of coffee intake and health outcomes.”
Journal reference:
- Wang, X., Ma, H., Sun, Q., Li, J., Heianza, Y., Van Dam, R. M., Hu, F. B., Rimm, E., Manson, J. E., & Qi, L. (2025). Coffee drinking timing and mortality in US adults. In European Heart Journal. Oxford University Press (OUP), DOI – 10.1093/eurheartj/ehae871, https://academic.oup.com/eurheartj/advance-article/doi/10.1093/eurheartj/ehae871/7928425