Men and women with large waists are at increased risk of dying young, a US study has found.
This is true regardless of their body mass index (BMI), research published in Archives of Internal Medicine suggests.
But very high waist measurements equivalent to UK size 24-26 in women and XXXXL in men appear to double the risk of mortality.
For the study researchers tracked more than 100,000 men and women aged 50 and older over nine years.
They also found that in women the link between a larger waist and a higher risk of death was strongest for those of normal weight.
More research is needed to find out why this is so, say the authors of the study.
Dr Eric Jacobs and his team at the American Cancer Society in Atlanta examined the link between waist circumference and risk of death among 48,500 men and 56,343 women.
Participants were predominantly white. At the start of the study, the average age of the men was 69 years and of the women, 67 years.
From 1997 until 2006 the deaths of any participants were tracked and the causes noted.
A total of 9,315 men and 5,332 women died during this time.
Whether participants were of normal weight, overweight or obese, researchers found that risk of death increased with increasing waist circumference.
This risk significantly increased in men with waists measuring 110cm or more and in women with waists measuring 95cm or more, the study found.
But it is only in men and women with very large waists (120cm or larger in men and 110cm in women) that the risk of death appears to double during the nine-year study.
The most common cause of death in those with the strongest link between mortality and waist size was respiratory disease, followed by cardiovascular disease and then cancer.
The study concludes: "Our results suggest that, regardless of weight, avoiding gains in waist circumference may reduce risk of premature mortality."
Dr David Haslam, chair of the National Obesity Forum, said the research is important.
"This underlines the message that fat inside the belly is dangerous.
"Even if you have a normal BMI and a big tummy then you are just as much at risk as someone who is classified as obese with a large tummy."
Previous studies have shown that abdominal obesity is a strong indicator for the development of coronary artery disease and is associated with insulin resistance and the development of Type 2 diabetes.
The risk is associated with the fat stores, which are not just under the skin but deep within the abdominal cavity.