Health consequences of obesity

 Health consequences of obesity

Mortality rates increase with BMI and they are greatly increased above a BMI of 30 kg/m^2. For example, a study in US women estimated that among people with a BMI .29 kg/m^2, 53% of all deaths could be directly related to their obesity.

As obesity has increased over the last 30 years, the prevalence of type 2 diabetes has increased dramatically.

The global numbers of people with diabetes (mainly type 2) are predicted to rise by almost 50% in 10 years—151 million in 2000 to 221 million in 2010. The most potent predictor for the risk of diabetes, apart from age, is the BMI. Even at a BMI of 25 kg/m^2 the risk of type 2 diabetes is significantly higher compared to BMI of less than 22 kg/m^2, but at BMI over 30 kg/m^2, the relative risks are enormous26. Type 2 diabetes is becoming increasingly prevalent among children as obesity increases in those age groups. This was first reported among the Pima Indians in 1979 where 1% of the 15–24-year-olds had diabetes (almost all type 2 diabetes). Now in many populations around the world, a substantial proportion of the teenagers with diabetes have the obesity-associated type 2 variety. Asian populations appear to develop diabetes at a lower BMI than other populations.

A high BMI is associated with higher blood pressure and risk of hypertension, higher total cholesterol, LDLcholesterol and triglyceride levels and lower HDLcholesterol levels. The overall risk of coronary heart disease and stroke, therefore, increases substantially with weight gain and obesity.

Gall bladder disease and the incidence of clinically symptomatic gallstones are positively related to BMI.

There is evidence to suggest increased cancer risk as BMI increases, such as colorectal cancer in men, cancer of the endometrium and biliary passage in women, and breast cancer in post-menopausal women. Obese people are also at increased risk of gout, sleep apnoea, obstetric and surgical complications.