DRINKING COFFEE ONLY IN THE MORNING LOWERS RISK OF DEATH FROM ANY CAUSE
Study shows having 2-3 cups is the ‘sweet spot’ for longevity, but daytime java drinkers don’t see enjoy the benefit.
NEW ORLEANS — Here’s some promising news for coffee enthusiasts, particularly those who prefer their caffeine fix in the morning hours. A new study examining over 40,000 American adults suggests that the timing of coffee consumption might be just as important as how much you drink when it comes to living a longer life.
Previous studies have established connections between moderate coffee consumption and various health benefits, including lower risks of Type 2 diabetes heart attack, and stroke.
“Research so far suggests that drinking coffee doesn’t raise the risk of heart disease, and it seems to lower the risk of some chronic diseases,” explains Dr. Lu Qi, HCA Regents Distinguished Chair and Professor at the Tulane University School of Public Health, in a statement. “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.”
Along with Qi, researchers from Harvard’s T.H. Chan School of Public Health and George Washington University identified two distinct patterns of coffee consumption among Americans. The first group, comprising 36% of participants, were “morning-type” drinkers who concentrated their coffee consumption between 4 a.m. and noon. The second group, making up 14% of participants, were “all-day-type” drinkers who spread their coffee intake throughout the day and into the evening hours. The remaining 48% were non-coffee drinkers.
Morning coffee reigns supreme
Following these individuals over a median period of 9.8 years revealed fascinating results. Morning coffee drinkers showed a 16% lower risk of death from all causes and a 31% lower risk of death from heart disease compared to non-coffee drinkers. In contrast, people who spread their coffee consumption throughout the day showed no significant reduction in mortality risk compared to non-drinkers.
The study, published in the European Heart Journal, found that the benefits appeared most pronounced for moderate coffee consumption, particularly among morning drinkers who consumed between two to three cups daily. These individuals demonstrated a 29% lower risk of all-cause mortality compared to non-coffee drinkers. Meanwhile, heavy coffee drinkers (more than three cups per day) saw a 21% lower risk of death, while light morning drinkers (one cup or less) still experienced a 15% lower risk.
Particularly notable were the heart benefits: moderate morning coffee drinkers showed a striking 48% reduction in death from heart complications. Heavy drinkers still had a 39% lower risk of cardiovascular death, while light drinkers enjoyed a 35% reduced risk.
These associations remained strong even after researchers accounted for various factors including age, sex, race, income, education, smoking status, and pre-existing health conditions.
“This is the first study testing coffee drinking timing patterns and health outcomes,” notes Dr. 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.”
But why might morning coffee be more beneficial?
Researchers proposed two potential mechanisms. First, afternoon or evening coffee consumption might disrupt our natural circadian rhythms, particularly through its effects on melatonin production. Previous clinical trials have shown that heavy coffee consumption later in the day can decrease nighttime melatonin production by 30%. Since melatonin plays a crucial role in regulating our biological clock and has been linked to cardiovascular health, disrupting its production might negate some of coffee’s potential benefits.
The second mechanism relates to coffee’s anti-inflammatory properties. Our bodies naturally produce higher levels of inflammatory markers in the morning, which gradually decrease throughout the day. Therefore, consuming coffee’s anti-inflammatory compounds during morning hours might provide maximum benefit when our bodies need it most.
As coffee remains one of the world’s most popular beverages, these findings could have significant public health implications. The 2015-20 U.S. Dietary Guidelines already recommend moderate coffee consumption as part of a healthy dietary pattern. This new research suggests that timing might be an additional factor to consider when making coffee-drinking decisions.
While the news might prompt some afternoon coffee enthusiasts to reconsider their habits, it’s worth noting that the study observed associations rather than direct cause-and-effect relationships. Still, for those seeking to maximize coffee’s potential health benefits, the morning hours might be the sweet spot.
Understanding the Numbers: A Deeper Look at Coffee’s Benefits
If you’re wondering why the overall benefit for morning coffee drinkers (16% lower mortality risk) seems smaller than the benefits for each specific consumption group (15%, 29%, and 21% lower risk), you’re not alone. This apparent contradiction actually reveals something interesting about how scientific studies analyze data.
Think of it like looking at a forest in two different ways. First, you might stand on a hilltop and look at the entire forest as one unit, measuring its overall characteristics. Then, you might walk through the forest and examine different types of trees separately, getting more specific measurements for each variety. Both approaches are valid but might give you slightly different insights.
In this study, researchers first looked at all morning coffee drinkers as one group, comparing them to non-coffee drinkers. This “forest-level view” showed a 16% lower mortality risk overall. Then they took a closer look, dividing morning coffee drinkers into three groups based on how much they consumed. This “tree-level view” revealed that moderate drinkers (2-3 cups) had the strongest benefit (29% lower risk), while light and heavy drinkers showed smaller but still significant benefits.
Why the difference? Several factors come into play:
- The analyses used different statistical methods and adjustments, much like using different measuring tools for different tasks.
- Not all consumption groups were equally sized. If more people fell into the categories with smaller benefits, this would pull down the overall average.
- The detailed analysis could capture nuances that the broader analysis missed, similar to how walking through the forest lets you notice details you couldn’t see from the hilltop.
Both sets of numbers are accurate within their respective analyses, and both tell us something important: morning coffee drinking appears beneficial regardless of how you analyze the data, with moderate consumption showing the strongest advantage.
This kind of complexity is common in scientific research, where looking at data from different angles helps build a more complete understanding of complex relationships between our behaviors and health outcomes.
Paper Summary
Methodology
The researchers analyzed data from the National Health and Nutrition Examination Survey (NHANES), studying dietary patterns of 40,725 adults. They specifically excluded participants who had pre-existing cardiovascular disease or cancer, as well as pregnant women and those reporting implausible caloric intake. Participants documented their food and beverage consumption through detailed 24-hour dietary recalls, noting not just what they consumed but exactly when throughout the day. To ensure their findings were robust, the team validated their results using data from a separate study (Women’s and Men’s Lifestyle Validation Study) involving over 1,400 adults who maintained comprehensive seven-day dietary records. The researchers used sophisticated statistical techniques, including cluster analysis, to identify patterns in coffee consumption timing and tracked mortality outcomes through the National Death Index until December 31, 2019.
Results
Over a median follow-up period of 9.8 years, the study recorded 4,295 deaths, including 1,268 from cardiovascular disease and 934 from cancer. Morning-type coffee drinkers consistently showed better health outcomes, with the strongest benefits observed in those consuming 2-3 cups daily. Importantly, while the researchers found significant associations between morning coffee consumption and reduced risk of all-cause and cardiovascular mortality, they found no significant association with cancer mortality. The positive associations remained strong even after the researchers adjusted for numerous potential confounding factors, including age, sex, race, income, education, smoking status, and pre-existing health conditions. The study also revealed that the timing of coffee consumption significantly modified the relationship between coffee intake amounts and mortality risk.
Limitations
The researchers acknowledge several important limitations. First, the observational nature of the study prevents establishing direct causation between coffee timing and mortality outcomes. Self-reported dietary data might include recall bias, and some potential confounding factors, such as shift work patterns or wake-up times, weren’t fully accounted for. The researchers also couldn’t exclude the possibility that morning coffee drinking might simply be a marker for an overall healthier lifestyle. Additionally, the study focused on US adults, so findings might not apply universally to other populations with different coffee-drinking cultures. Genetic information wasn’t available, preventing analysis of how genetically determined caffeine metabolism rates might interact with timing patterns.
Discussion and Key Takeaways
This groundbreaking study introduces timing as a crucial factor in coffee consumption’s health effects, potentially explaining some inconsistencies in previous research about heavy coffee consumption. The findings suggest that morning coffee consumption might optimize the beverage’s health benefits, particularly regarding cardiovascular health. The research also highlights the importance of considering circadian rhythms in dietary choices, suggesting that the timing of nutrient intake might be just as important as the amount consumed. The study’s findings could have significant implications for public health recommendations regarding coffee consumption, though more research is needed to understand the precise mechanisms behind these associations.
Funding and Disclosures
The study received substantial support from various National Institutes of Health grants, including funding from the National Heart, Lung, and Blood Institute (grants HL071981, HL034594, and HL126024) and the National Institute of Diabetes and Digestive and Kidney Diseases (grants DK115679, DK091718, DK100383, and DK078616). The Women’s and Men’s Lifestyle Validation Study received additional NIH funding through multiple grants. The researchers declared that the funding sources and sponsors had no role in the study’s design, data collection, analysis, manuscript preparation, or decision to publish.
Publication Information
This research appears in the European Heart Journal (2025), authored by Xuan Wang and colleagues from various institutions including Tulane University, Harvard T.H. Chan School of Public Health, Brigham and Women’s Hospital, and The George Washington University. The paper is available as an open-access article under Creative Commons Attribution License terms, allowing unrestricted reuse and distribution with proper citation.