Professor Mike Lean of the University of Glasgow's Department of Human Nutrition has co-authored a paper revealing that in future your chances of cardiovascular disease could be assessed by the size of your trousers.

A study published in the Journal of Human Nutrition and Dietetics, in collaboration with the British Dietetic Association, looked at 200 men and 160 women taking part in a larger research project in Glasgow. Detailed measurements were taken of waist circumference, and weight and height to calculate body mass index (BMI). In addition, blood pressure was measured and health status data were obtained relating to ischaemic heart disease and diabetes.

The BMI score is the standard marker for describing obesity in populations, but in clinical practice, a more accurate method for predicting cardiovascular risk is by waist circumference measurement. High waist fat values ('apple' shaped people) consistently relate to all components of metabolic syndrome (hypertension, insulin resistance and altered blood lipids). From this data, action levels relating to disease risk have been agreed: action level 1 (94cm in men, 80cm in women) indicates some risk; action level 2 (102cm in men, 88cm in women) indicates significantly increased risk.

It is no surprise that the researchers found a strong link between clothing size and both BMI and waist circumference. But through mathematical modelling, the researchers were able to demonstrate that the action level 1 cut offs were UK waist size 34 trousers for men and a UK dress size of 14 for women. Action level 2 cut offs were size 36 trousers for men and a dress size of 16 for women.

Further analysis supported the pattern of measured or documented increased cardiovascular risks with larger wardrobe. Trousers over waist size 38 in men indicated a nearly four-fold chance, and women with a dress size above 18 had a seven-fold chance of having at least one of the main cardiovascular risk factors.

People may not always be sure of their weight, or be unwilling to reveal this, but only about 2% of the people in the study were wrong about their garment size. Providing there is clothing industry consistency with dress and trouser size specifications, clothing cut offs could be the new way to support meaningful public understanding of when the risks of being fat need action.

Kate Richardson (K.richardson@admin.gla.ac.uk)

1. Reference: Clothing size as an indicator of adiposity, ischaemic heart disease and cardiovascular risks. TS Han, E Gates, E Truscott, MEJ Lean Journal of Human Nutrition and Dietetics (2005) 18, pp1-8

2. Contact researcher: Professor MEJ Lean, University Department of Nutrition. Glasgow Royal Infirmary Tel 0141 211 4686 email lean@clinmed.gla.ac.uk

3. Media enquiries to the British Dietetic Association should be directed to Amanda Johnson (01908 564 012) or Frankie Phillips (01626 362 473) email pr@bda.uk.com

4. The British Dietetic Association, founded in 1936, is the professional Association for registered dietitians in Great Britain and Northern Ireland. It is the nation?s largest organisation of food and nutrition professionals with over 5,000 members. About two-thirds of members are employed in the National Health Service. The remaining members work in education, industry, research, sport settings or freelance. Registered dietitians hold the only legally recognised graduate qualification in nutrition and dietetics. They are experts in interpreting and translating the science of nutrition into practical ways of promoting nutritional well-being, disease treatment and the prevention of nutrition-related problems. Their advice is sound and based on current scientific evidence. Registration, awarded by the Health Professionals Council, is an indication that a dietitian is fit to practise and is working within an agreed statement of conduct.

First published: 8 December 2005