Excessive coffee drinking has no benefits

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Latte, cappuccino or short black coffee, morning coffee is a necessity for many people who want to start their day right. While the humble coffee may be an important feature of your daily grind, how much is too much?

While the pros and cons of drinking coffee have been debated for decades, new research from the University of South Australia suggests that drinking six or more cups a day can have adverse effects on your health, increasing your risk of heart disease by 22 percent.

One in six Australians has cardiovascular disease. It is a leading cause of death, with one person dying from it every 12 minutes. According to the World Health Organization, cardiovascular disease is the leading cause of death, yet one of the most preventable.

Investigating the link between long-term coffee consumption and cardiovascular disease, University of South Australia researchers Dr Ang Zhou and Professor Elina Hyppönen from the Australian Centre for Precision Health said their study confirmed that excessive caffeine can lead to high blood pressure, a precursor to heart disease.

This is the first time an upper limit has been established for safe coffee consumption and cardiovascular health.

“Coffee is the most commonly consumed stimulant in the world – it wakes us up, increases our energy and helps us concentrate – but people always ask 'how much caffeine is in it?',” Professor Hyppönen said.

“Most people would agree that if you drink a lot of coffee, you may feel jittery, irritable, or even nauseous – this is because the caffeine helps your body work faster and harder, but it can also be a sign that you may have reached your limit for the time being.

“We also know that the risk of cardiovascular disease increases with high blood pressure, which is a known consequence of excessive caffeine consumption.

“To maintain a healthy heart and healthy blood pressure, people must limit coffee to less than six cups a day – six is ​​the tipping point where caffeine starts to have a negative impact on cardiovascular risk, according to our data.”

Using data from 347,077 participants aged 37-73 years from UK Biobank, the study explored the ability of a caffeine metabolism gene (CYP1A2) to better process caffeine, identifying an increased risk of cardiovascular disease consistent with coffee consumption and genetic variation.

Professor Hyppönen said that although carriers of the rapid processing gene variant were four times faster at metabolising caffeine, the research did not support the idea that these people could safely consume higher amounts of caffeine without experiencing harmful health effects.

"An estimated three billion cups of coffee are consumed every day around the world," Professor Hyppönen said.

“It’s necessary to understand what’s good for you and what limits are good for you.

"As with many things, it's all about moderation; overindulge and your health will pay the price." #清风计划#

More information: Ang Zhou et al., Long-term coffee consumption, genetics of caffeine metabolism, and cardiovascular disease risk: a prospective analysis of up to 347,077 individuals and 8368 cases, American Journal of Clinical Nutrition (2018). DOI: 10.1093/ajcn/nqy297

Journal information: American Journal of Clinical Nutrition