Are you about to have your third cup of coffee for the day, and feeling guilty about it?
Don’t. Your coffee addiction could make you live longer.
A study by Harvard University suggested that people who drank three to five cups of coffee per day were less likely to die prematurely from heart disease, suicide, diabetes and Parkinson’s disease.
The Chan School of Public Health researchers found that the benefits applied to those who drank caffeinated and decaffeinated coffee, and also included a lower risk of death from cardiovascular disease, neurological diseases, type 2 diabetes, and suicide.
Experts say coffee consumption can be part of a healthy diet.
“This study provides further evidence that moderate consumption of coffee may confer health benefits in terms of reducing premature death due to several diseases,” senior author Professor Frank Hu said in a statement.
The study compared people who did not drink coffee, or drank less than two cups daily, to those who reported drinking “moderate” amounts of coffee, or up to five cups daily.
It did not definitively prove cause-and-effect, but did uncover an apparent link that aligned with previous research, which scientists would like to probe further.
No protective effect was found against cancer in the study, which was published in the latest edition of the journal Circulation.
Some previous research pointed to a link between coffee consumption and a lower risk of certain cancers.
The research also did not specify how the sample group drank their coffees – for example with milk or sugar.
Despite benefits, coffee not suited to everyone
The study spanned over 30 years and was based on data gathered from three large, ongoing surveys including 300,000 nurses and other health professionals.
The sample group agreed to answer questionnaires about their own medical conditions and habits at regular intervals during the course of that period.
Researchers also accounted for potential confounding factors such as smoking, body mass index, exercise, alcohol consumption and diet.
The effects were more evident when researchers discounted smokers. They found non-smokers who drank coffee were between eight and 15 per cent less likely to die, depending on how much they drank.
But the fact the research relied on surveys, which used self-reported behaviour, could raise questions about its reliability.
Experts warned that coffee – a substance adored by many devotees – may not be right for everyone.
“Regular consumption of coffee can be included as part of a healthy, balanced diet,” author Professor Hu said.
“However, certain populations, such as pregnant women and children, should be cautious about high caffeine intake from coffee or other beverages.”
Your liver’s response to caffeine
Meanwhile, separate research by Monash University revealed drinking two or more cups of a coffee each day can ward off liver diseases.
It showed two cups each day found to reduce the damage caused by hepatitis C by up to 13 per cent.
For people with fatty liver – the most common form of liver disease, affecting more than one in 10 Australians – drinking four coffees a day was shown to reduce liver stiffness by 24 per cent.
Monash University gastroenterologist Alex Hodge said it was the caffeine that could help fight liver disease and other conditions.
Dr Hodge, a liver specialist at Monash Health Clinic, is currently in San Francisco presenting his findings to the annual meeting of the American Association for the Study of Liver Diseases.
The study of 1100 liver disease patients at the Monash Health Clinic showed that even when other risk factors such as weight, alcohol consumption and smoking were taken into account, coffee was able to reduce the impact of their conditions.
“I certainly wouldn’t advocate drinking 20 cups a day, but a moderate intake of coffee, particularly if you have liver disease, is certainly something you shouldn’t shy away from,” Dr Hodge said.
“This is specifically coffee. Caffeine is one of a thousand substances contained in coffee, so it is probably more than just the caffeine. Depending on the liver disease a person has, the effects vary.”
Dr Hodge said the research cannot yet explain which type of brew was best and which of those were the best at helping the liver.
He also suggested using “common sense” with those who might be sensitive to caffeine or suffered anxiety.
“Liver disease does not give you symptoms until it’s too late, so there is no harm in having moderate amounts of coffee.”
– with ABC