A major study involving more than 14,000 people in Finland, which has the highest rate of coffee consumption in the world, has revealed that those who drink most have the lowest incidence of adult-onset or type 2 diabetes.
When people drank three to four cups of coffee a day, their risk of developing diabetes fell by 29 per cent for women and 27 per cent for men.
Coffeeholics – who drank very large amounts of coffee – ten or more cups a day – were even less likely to suffer from the disease: such high consumption reduced the risk by 79 per cent for women and 55 per cent for men.
Jaakko Tuomilehto, who led the research, said it suggested that coffee drinking offered some protection against adult-onset diabetes, particularly in women.
Excessive coffee drinking has been linked to a range of health problems, including miscarriage, insomnia, anxiety, diarrhoea and an irregular heartbeat. Most nutritionists advise against drinking more than four cups a day, particularly during pregnancy.
Type 2 diabetes, which usually develops in middle age and is often linked to obesity, has become a worldwide epidemic. While it can be controlled by diet and drugs, it can have long-term consequences such as heart disease and blindness.
The condition develops when the body becomes insensitive to insulin. Coffee reduces insulin sensitivity but other components in it, such as magnesium or chlorogenic acid, may have beneficial effects.