Waist measurement and obesity

Waist measurement is a measurement which indicates the need for weight management and reflects coronary risk related to both overweight and a central fat distribution.

A 'raised' waist circumference is defined as above 102 cm (40 inches) for men and above 88 cm (35 inches) for women

• however, the International Diabetes Federation has suggested lower cutoff points (of 94 cm (37 inches) in men and 80 cm (31.5 inches) in women) for measuring metabolic syndrome. These lower cutoffs have been adapted for different populations (see table below):

Excess body fat contributes to around 58% of cases of type 2 diabetes, 21% of heart disease and between 8% and 42% of certain cancers (breast, colon and endometrial)

• however, the point at which the level of body fat becomes risky to health varies between ethnic groups - this is reflected in the ethnic specific waist measurements that suggest central obesity
  
  
  
• waist circumference thresholds as a measure of central obesity

Ethnic south and central Americans

• use south Asian recommendations until more specific data are available

Sub-Saharan Africans

• use European data until more specific data are available

Eastern Mediterranean and middle east (Arab) populations

• use European data until more specific data are available

NICE have suggested that management of obesity takes into consideration body mass index, waist circumference and presence of co-morbidities (2):

Obesity is graded according to the Body Mass Index (BMI):

• Healthy weight 18.5-24.9
• Overweight 25-29.9
• Obesity I 30-34.9
• Obesity II 35-39.9
• Obesity III 40 or more

The approach to management of obesity depends on the severity of obesity, the waist circumference, and any accompanying risk factors for complications:

• Overweight patients
  • if no comorbidities present
    • low waist circumference - general advice on healthy weight and lifestyle
    • high waist circumference - diet and physical activity
    • very high waist circumference - diet and physical activity
  • if comorbidities present
    • diet and physical activity; consider drugs
• Obesity I patients
  • if no comorbidities present
    • low waist circumference - diet and physical activity
    • high waist circumference - diet and physical activity
    • very high waist circumference - diet and physical activity
  • if comorbidities present
    • diet and physical activity; consider drugs
• Obesity II patients
  • if no comorbidities present
    • low waist circumference - diet and physical activity; consider drugs
    • high waist circumference - diet and physical activity; consider drugs
    • very high waist circumference - diet and physical activity; consider drugs
  • if comorbidities present
    • diet and physical activity; consider drugs; consider surgery
• Obesity III patients - Diet and physical activity; consider drugs; consider surgery

Notes:

• the level of intervention should be higher for patients with comorbidities, regardless of their waist circumference. The approach should be adjusted as needed, depending on the patient's clinical need and potential to benefit from losing weight
  
  
  
  

Reference:

1. NICE (July 2013).Assessing body mass index and waist circumference thresholds for intervening to prevent ill health and premature death among adults from black, Asian and other minority ethnic groups in the UK
2. NICE (November 2014). Obesity guidance