Coffee and your health
The potential health benefits and drawbacks of coffee
Coffee drinking is a hot topic. In the UK we drink about 70 million cups of the stuff every day. If we're not having a mug at home we're popping into a coffee shop or cafes.
Coffee may taste good and get you going in the morning, but what will it do for your health?
A growing body of research shows that coffee drinkers, compared to non-drinkers, are less likely to have type 2 diabetes, Parkinson's disease, and dementia. It's also suggested that coffee drinkers have fewer cases of certain cancers, heart rhythm problems and strokes.
"There is a wealth of evidence which shows that moderate coffee consumption, of four to five cups a day, is safe and can form part of a balanced diet", according to Dr Euan Paul, who is spokesman for the British Coffee Association.
"When consumed in moderation, coffee may lower hypertension, diabetes and the risk of certain cancers."
Coffee isn't proven to prevent those conditions.
Researchers don't ask people to drink or skip coffee for the sake of science. Instead, they ask them about their coffee habits. Those studies can't show cause and effect. It's possible that coffee drinkers have other advantages, such as healthier diets, more exercise, or protective genes.
So there isn't any solid proof but there are signs of potential health perks and a few cautions.
Here is a condition-by-condition look at the research.
Type 2 diabetes
The evidence published to date suggests that coffee may be protective against developing type 2 diabetes.
In 2009 Dutch scientists claimed that drinking at least three cups of tea or coffee a day can reduce your risk of developing type 2 diabetes by 42%.
The team from the Julius Centre for Health Sciences and Primary Care, University Medical Centre in Utrecht, evaluated questionnaires filled in by 40,000 people. They concluded: "Both coffee and tea consumption were associated with a lowered risk of type 2 diabetes. Blood pressure and intake of magnesium, potassium and caffeine did not explain these associates."
Commenting on the Dutch research, Dr James Pickett, Research Officer at Diabetes UK, said: "This is interesting research. However it does not prove that coffee and tea protect against type 2 diabetes. This is because it is impossible to know what other factors might affect a person's risk of developing the condition."
Frank Hu, who is professor of nutrition and epidemiology at Harvard School of Public Health in the United States calls the data on coffee and type 2 diabetes "pretty solid," based on more than 15 published studies.
"The vast majority of those studies have shown a benefit of coffee on the prevention of diabetes. And there is also evidence that decaffeinated coffee may have the same benefit as regular coffee," Professor Hu tells us.