A bulging waistline can almost double the risk of dying early, even for people who are not overweight, doctors have found.

The finding emphasises that weight alone is not a good guide to health, and that storing excess fat around the midriff can have a serious impact on lifespan.

A study of more than 350,000 Europeans showed that women with 39.4in (100cm) waists were almost twice as likely to die prematurely as those with 25.6in (65cm) waists. In men, the same higher death rate was linked with a waistline of 47.2in (120cm), compared with those who measured 31.5in (80cm).

Researchers explain in the New England Journal of Medicine that excess fat around the midriff may increase the risk of serious conditions, such as cancer and heart disease, by releasing hormones and compounds that help them to develop.

Doctors at Imperial College London and the German Institute of Human Nutrition examined the body mass index (BMI) and waist to hip ratios of 359,387 people, more than 14,000 of whom died during the 10-year study. They found that for every 5cm increase in waist measurement, the risk of premature death rose by 17% in men and 13% in women.

Those with a large BMI tended to die of heart disease and cancer, while respiratory diseases were more common among skinnier people. Those with the lowest risk of early death were men with a BMI of 25.3 and women with a BMI of 24.3.

"The most important result is the finding that not just being overweight, but also the distribution of body fat, affects the risk of premature death of each individual," said Elio Riboli, who led the study.

June Davison, a cardiac nurse at the British Heart Foundation, said: "The risk of developing heart disease is higher when fat is concentrated around the waist area. If you tend to gather weight around your middle, increasing the amount of activity you do and watching what you eat will help to reduce your risk of heart disease and of dying early."