A new study of 3,000 people has claimed men and women with thighs over 60cm (23.6in) in circumference have a lower risk of heart disease and early death.
People with narrow thighs may not have enough muscle mass to use insulin properly, raising the risk of diabetes and, in turn, heart disease, the researchers say.
Further investigation needed
Experts, however, cautioned that the research needed further investigation before any definite conclusions could be drawn.
The study, published in the British Medical Journal, followed men and women in Denmark for more than 10 years. They were measured for height, weight and thigh, hip and waist circumference and their overall percentage of body fat was calculated.
Researchers also looked at the activity levels of the participants, whether they smoked, their blood pressure and cholesterol levels. Incidence of heart disease over 10 years and death rates over 12-and-a-half years were then measured.
"The increased risk was independent of abdominal and general obesity and lifestyle and cardiovascular risk factors such as blood pressure", said lead researcher Professor Berit Heitmann.
"Additionally we found that the risk was more highly related to thigh circumference than to waist circumference.
"It's a very simple, very crude measure but it seems to have an individual effect. And it may be a way for doctors to assess risk.
"The nice thing is that if you have a small thigh you can do something about it through exercise."
Little clinical value
Dr Iain Frame, Director of Research at Diabetes UK, said: “Waist circumference and Body Mass Index (BMI) have previously been shown to be good measures to predict cardiovascular risk, along with other measures such as hip circumference and waist-hip ratio. This study investigated whether thigh circumference could be used an indicator for risk of cardiovascular disease.
“The study, however, used only a small sample size and after the data had been fully adjusted to remove known risk factors and analysed the authors concluded measuring thigh circumference would be unlikely to be of any value clinically.
“It is crucial to stress that the results of this research do not show that having large thighs will reduce your risk of developing cardiovascular disease.
"Waist measurement and BMI indicators are the best way to measure risk of cardiovascular complications and of Type 2 diabetes.”