Anyone who's had a coffee-induced anxiety attack and sworn that they've felt their heart actually skip a beat will find little comfort in a recent article published by online journal BMC Medicine.
The study looked at the link between coffee consumption and the incidence of atrial fibrillation (AF), which is the fancy name for the two upper chambers of the heart contracting either too quickly or in an irregular manner. AF is the most common type of cardiac arrhythmia, a condition which can cause poor blood circulation.
"This is largest prospective study to date on the association between coffee consumption and risk of atrial fibrillation. We find no evidence that high consumption of coffee increases the risk of atrial fibrillation," Susanna Larsson, associate professor of epidemiology at the Karolinska Institute in Sweden and lead author on the study, said in a statement. "This is important because it shows that people who like coffee can safely continue to consume it, at least in moderation, without the risk of developing this condition."
Larsson's team followed 41,881 men and 34,594 women for 12 years. During the follow-up period, they used the Swedish Hospital Discharge Register to determine which patients developed atrial fibrillation. Of the 75,000 or so participants, the Swedish researchers found 4,311 male and 2,730 female incidents of AF, but, having tracked their coffee consumption, failed to find any statistically significant link between the two.
If anything, the results suggest that coffee could be potentially beneficial for the heart. Larsson and her co-authors also looked at six other studies and found that "low caffeine intake but not moderate and high intakes was associated with a reduced risk of AF," their article states.
Another interesting finding was that the sexes may not process caffeine in the same manner. "In sex-specific analyses, coffee consumption was associated with a non-significant positive association in men, but with a non-significant inverse association in women," they wrote in BMC Medicine. "Whether men may be more sensitive to a high coffee or caffeine intake warrants further study."
But aside from its addictive qualities, and the occasional anxiety attack, health researchers have been hard-pressed to find the downside of drinking coffee. Instead this study falls in line with the pile of research papers that point to coffee's health benefits like alleviating jet-lag, curing weed addiction, improving mood, and helping to reduce the risk of getting cancer.