Coffee has had a bad press but experts now say you can enjoy your favourite pick-me-up without feeling guilty.

Dr Chiara Trombetti believes the benefits of the beverage could out-weigh the risks and, according to her research, the stronger the brew the better.

Dr Trombetti, a dietitian at the Humanitas Gavezzeni Institute in Bergamo, northern Italy, said coffee contained anti-oxidants and tannin which protect the heart.

Meanwhile, American scientists at the Harvard School of Public Health said the risk of type-2 diabetes could be halved by drinking at least six cups of coffee a day.

Type-2 diabetes occurs when the body becomes resistant to insulin, which enables the cells to absorb energy-giving glucose.

The Harvard research was backed up by research in Finland which found drinking coffee could reduce the risk of non-insulin dependent diabetes.

Katie Clarke, community dietitian for Brighton and Sussex University Hospitals NHS Trust, said although caffeine had been blamed for high blood pressure, heart problems, headaches, insomnia and dehydration, moderate coffee drinking would not harm people.

Regular, moderate drinking had no influence on high blood pressure and there was little evidence caffeine consumption increased the risk of coronary heart disease or had any effect on the development of cancer.

She said: "The bottom line is a moderate intake of caffeine isn't going to do you any harm. But for pregnant women, it is especially important to keep it moderate as high levels of caffeine can lead to low birth weight or miscarriage.

"If you are drinking more than three to four cups a day, then consider cutting back."