A City Guide To Huai’an for et al. H – R I S K n normal weight’ if their BMI is between and ; n mildly obese grade if their BMI is between and generally referred to as overweight; n moderate or clinically obese grade if their BMI falls between and .; n severely obese grade if their BMI is or greater. Negative health consequences of obesity As noted at the outset of this chapter, being underweight is the largest global cause of mortality yet a growing number of people, predominantly in Western or developed countries, are at risk from the opposite problem ? obesity. Obesity is a major risk factor in a range of physical illnesses, including hypertension, heart disease, Type diabetes, osteoarthritis and lower back pain. The relative risk of disease appears to increase proportionately in relation to the percentage overweight a person is, although evidence as to this linear relationship remains mixed. The longitudinal Framingham heart study shows a relationship between obesity and mortality which appears over the long term two?three decades, with the risk of death within twenty-six years being increased by per cent per extra pound in weight in those aged between and , and by per cent per extra pound in those aged to The J-shaped curve shown in Figure also reminds us of the risk of being underweight, with the lowest mortality in those within the ideal weight range body mass index Obesity is also implicated in psychological ill-health including low selfesteem and social isolation British Medical Association a; Strauss ; among Australian children, for example, it has been associated with poorer health-related quality of life Williams et al O B E S I T Y Prevalence of obesity The European Commission estimates that per cent of the EU adult population is overweight, with a further per cent reaching weights defined as clinically obese. A City Guide To Huai’an 2016.