» Study finds there is such a thing as too much coffee
"In order to maintain a healthy heart and a healthy blood pressure, people must limit their coffees to fewer than six cups a day — based on our data six was the tipping point where caffeine started to negatively affect cardiovascular risk," professor Elina Hyppönen, one of the study’s researchers said.
That study found that people who drink one to two cups of caffeinated coffee a day had a lower risk of cardiovascular disease than people who drank decaf or no coffee at all. But for individuals who consumed six or more cups of caffeinated coffee a day, the risk of cardiovascular disease increased 22%.
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"There is much more reason to be concerned about a host of other dose-related effects, from blood pressure elevation, to heart rate elevation, to cardiac dysrhythmias," David Katz, a director at the Yale-Griffin Prevention Research center and author of "The Truth About Food," told HuffPost. "More importantly, extreme coffee consumption is likely to be associated with harms unrelated to the heart, such as insomnia, agitation, and possibly a range of other metabolic effects, from microbiome to bone density."
Professor Metin Avkiran, associate nedical director at the British Heart Foundation, said: "Understanding the impact that coffee has on our heart and circulatory system is something that researchers and the media have had brewing for some time.
"There are several conflicting studies saying different things about coffee, and it can be difficult to filter what we should believe and what we shouldn't. This research will hopefully put some of the media reports in perspective, as it rules out one of the potential detrimental effects of coffee on our arteries."
Fung added: "The main message for people to take away from this is that coffee can be enjoyed as part of a healthy lifestyle, and coffee lovers can be reassured by this result in terms of blood vessel stiffness outcomes.
"We're not telling people to drink 25 cups a day per se. If anything, if you drink within recommended guidelines, then we don't expect to see an increase in arterial stiffness compared with those who drink one cup or less a day."
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