Consuming 2 to 3 cups of coffee a day is associated with a reduced risk of cardiovascular disease (CVD) and may be associated with living longer, according to 3 studies being presented at the American College of Cardiology’s (ACC) 71st Scientific Sessions, held April 2-4, 2022.
“Because coffee can quicken heart rate, some people worry that drinking it could trigger or worsen certain heart issues. This is where general medical advice to stop drinking coffee may come from. But our data suggest that daily coffee intake shouldn’t be discouraged, but rather included as a part of a healthy diet for people with and without heart disease,” said senior author Peter M. Kistler, MD, PhD, professor, head of arrhythmia research, Alfred Hospital, Baker Heart and Diabetes Institute, Melbourne, Australia, in an ACC press release. “We found coffee drinking had either a neutral effect—meaning that it did no harm—or was associated with benefits to heart health.”
Kistler and colleagues used data from the UK BioBank, a large-scale prospective health database with information from more than half a million individuals who were followed for approximately 10 years. Investigators analyzed levels of coffee consumption ranging from 1 cup to over 6 cups per day and the association with arrhythmias; CVD, including coronary artery disease (CAD), heart failure (HF), and stroke; and total and cardiovascular-related mortalities among persons with and without CVD.
Coffee consumption was obtained from participant questionnaires and divided into the following groups: 0, <1, 2-3, 4-5, >5 cups of coffee per day.
For the first study, Kistler et al. examined data from 382 535 persons without known CVD to assess whether coffee consumption was associated with the development of CVD or stroke during 10 years of follow-up. The average age of participants was 57 years and 52% of the total cohort were women.
Results showed that in general, consuming 2-3 cups of coffee per day was associated with the greatest benefit, translating to 10%-15% lower risk for CVD, CAD, HF, and all-cause mortality, according to the press release. Also, the risk of stroke was lowest when participants drank <1 cup of coffee/day. The team observed a U-shaped relationship between higher coffee intake and incident arrhythmia, with the lowest risk at 2-3 cups/day.
The second study included 34 279 persons with some form of CVD at baseline. Kistler and his team found that consuming 2-3 cups of coffee/day was associated with reduced odds of all-cause mortality compared with drinking no coffee. Consuming any amount of coffee was not associated with a higher risk of abnormal heart rhythms, including atrial fibrillation (AF) or atrial flutter, which is often what clinicians are concerned about, Kistler said in the press release.
Among the 24 111 participants who had an arrhythmia at baseline, coffee intake was associated with a lower risk of mortality. For example, participants with AF who consumed 1 cup/day were approximately 20% less likely to die than non-coffee drinkers.
Kistler noted that while 2-3 cups of coffee/day seemed to be the most favorable overall, individuals should not increase their coffee consumption, especially if it makes them feel anxious or uncomfortable.
In a third study, the team analyzed the relationship between CVD and the type of coffee consumed: ground, instant, or decaffeinated. Results showed that the lowest risk for CVD was observed at 2-3 cups/day for ground and instant coffee. All 3 coffee types were shown to reduce mortality, and decaffeinated coffee had a neutral effect against incident arrhythmia and CVD, except for HF. These findings suggest that caffeinated coffee is preferable across the board and there are no CV benefits to choosing decaffeinated over caffeinated coffee, said Kistler.
All 3 studies had several limitations, including the fact that investigators could not control for dietary factors that could affect CVD, nor were they able to adjust for any creamers, milk, or sugar consumed. In addition, participants were mainly White and further studies are needed to determine whether these findings extend to other populations. Coffee intake was based on self-reported questionnaires and should be considered when interpreting these findings, although Kistler said that research suggests individuals’ dietary habits do not significantly change in adulthood or over time. The results should be validated in randomized clinical trials, added Kistler.