title: Overweight and obesity in students of a dental college of Karachi: lifestyle influence and measurement by an appropriate anthropometric index.
abstract: OBJECTIVE
  To compare body mass index (BMI), waist circumference (WC), and body fat percentage (%BF), as index of overweight and obesity in young adults. We also intended to find an association between lifestyle behaviours and obesity.
  
  
  METHODS
  A cross-sectional study was conducted at Fatima Jinnah Dental College, Karachi, during 2007 to 2008, with 192 first year dental students, (18-21years) of high socioeconomic class. All were questioned regarding lifestyle behaviours. Overweight and obesity were estimated by measuring %BF, BMI, and WC. For %BF, skinfold thickness was measured using skinfold calipers. BMI > or = 23.0-24.9 kg/m2 was taken as overweight and > or = 25.0 kg/m2 as obese (Asians criteria proposed by Western Pacific Regional Office of World Health Organization). WC using Asian cutoff values for overweight and obesity were: males > or = 78 cm and > or = 90 cm; females > or = 72 cm and > or = 80 cm, respectively. Body fat percentage used to define overweight and obesity was: males 22.1-27.0 and > 27.1; females 27.1-32.0 and > 32.1, respectively. Pearson's correlation was done between the BMI, WC and %BF with statistical significance taken at P < 0.01.
  
  
  RESULTS
  BMI (Expressed as mean +/- SD) in males and females was 23.82 +/- 3.88 and 20.98 +/- 4.12 respectively. WC was 83.63 +/- 10.20 cm in males and 70.22 +/- 9.36 cm in females. %BF was 22.32 +/- 6.27 in males and 28.73 +/- 6.65 in females, with an overall 60.8% females and 44.4% males found to be overweight or obese. Obesity was underpredicted by BMI when compared to skinfold calipers method. The obese were seen to skip breakfast more often [odds ratio (OR): 2.39], take frequent snacks (OR: 1.58), watch television more (OR: 1.58), and were physically less active than their non-obese counterparts.
  
  
  CONCLUSIONS
  Body fat percentage using skinfold caliper is a reliable index of obesity. Lack of sleep and skipping of breakfast, are prominent promoters of obesity, in addition to other lifestyle behaviours.
authors.affiliation: Department of Physiology, Fatima Jinnah Dental College, Karachi, Pakistan.
authors.forename: Mozaffer Rahim
authors.initials: MR
authors.lastname: Hingorjo
authors.forename: Sadiqa
authors.initials: S
authors.lastname: Syed
authors.forename: Masood Anwar
authors.initials: MA
authors.lastname: Qureshi
mesh_terms: D000293:Adolescent; D001823:Body Composition; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D015438:Health Behavior; D006305:Health Status Indicators; D006801:Humans; D008019:Life Style; D008297:Male; D009765:Obesity / Q000145:classification / Q000453:epidemiology*; D016017:Odds Ratio; D050177:Overweight / Q000145:classification / Q000453:epidemiology*; D010154:Pakistan / Q000453:epidemiology; D012307:Risk Factors; D012575:Schools, Dental / Q000706:statistics & numerical data*; D012885:Skinfold Thickness; D013223:Statistics as Topic; D013335:Students, Dental / Q000706:statistics & numerical data*; D055105:Waist Circumference; D055815:Young Adult