Apple-shaped women with a big waist have a higher risk of developing asthma - even if they have a normal body weight, according to US experts.
While added weight is known to raise the risk of asthma, this study found weight around the abdomen was particularly important.
The study analysed data on 88,300 females, finding that those who were overweight were 40 per cent more likely to have asthma compared to women of a normal weight.
Women of normal body weight, but with a waist circumference of more than 88cm were also at increased risk - around a third higher than those with a smaller waist, said the journal Thorax.
Abdominal, or visceral, fat is metabolically more active than other types of body fat and can produce compounds that may cause inflammation related to asthma.