Four cups of coffee a day could be killing you

Staff Writers
August 16, 2013
News Limited Network

COFFEE: It’s the cornerstone of modern life. But too much of a good thing could be hurting you – particularly if you are under 55.
A study published in the journal Mayo Clinic Proceedings indicates that drinking more than 28 cups of coffee a week can significantly boost your chance of death.

The figures show a 50 per cent increase in deaths from all causes for heavy coffee drinkers aged under 55 years.

The American study examined the coffee habits and lifestyles of 45,000 people and found an overall 21 per cent increase in mortality among those who sipped their way through more than four cups a day.

If you’re over 55, it doesn’t seem to matter. No adverse affects were correlated to how much coffee you drink.

The study hypothesises that the association between coffee and mortality may be due to the interaction of age and coffee consumption, combined with genetic coffee addiction.

“Coffee has long been suspected to contribute to a variety of chronic health conditions … (but) the results are often controversial,” a statement from the researchers reads.

Coffee is a complex mixture of chemicals, and is generally regarded as a positive source of antioxidants and have minor anti-inflammatory properties. It’s stimulant effect is, of course, the best known attribute.

Choose your poison: Coffee increases epinephrine levels, inhibit insulin activity, increases blood pressure and levels of homocysteine
“However, it is also well-known that coffee has potential adverse effects because of caffeine’s potential to stimulate the release of epinephrine, inhibit insulin activity, and increase blood pressure and levels of homocysteine,” the lead researchers say.

“Thus, all of these mechanisms could counterbalance one another.”

This study, involving several different research groups, sought to reduce that controversy by conducting the large scale study of people aged between 20 and 87. These people filled out medical history questionnaires which assessed their lifestyle and personal and family medical histories.

The research also suggests that heavy coffee drinkers face additional risks through genetic mechanisms and other risk factors with which coffee drinking is associated.

The study notes those who consumed large amounts of coffee were also more likely to smoke and have lower levels of fitness.
During the 17-year follow-up, there were 2512 deaths among the 43,727 participants.

“Younger men had a trend towards higher mortality even at lower consumption, but this became significant at about 28 cups per week where there was a 56 per cent increase in mortality from all causes,” the statement reads.

“Younger women who consumed more than 28 cups of coffee per week also had a greater than twofold higher risk of all-cause mortality than those who did not drink coffee.”

The researchers recommend that younger people should avoid having more than four coffees a day.

“There continues to be considerable debate about the health effects of caffeine, and coffee specifically, with some reports suggesting toxicity and some even suggesting beneficial effects,” cardiovascular expert Dr Carl Lavie said.