obesity

introduction

Obesity, defined by the World Health Organization as a body mass index (BMI) greater than 30 kg/m², is an ever increasing problem in most regions of the world. It is estimated that, in 2005, there were more than 400 million obese individuals over the age of 15 worldwide and this number is projected to rise to over 700 million by 2015.

The prevalence of obesity among adults in the US is 32.2% and the number of obesity -related deaths, could be up to 300,000 per year. The prevalence of obesity in Europe varies by country, but is as high as 20% for men and 30% for women.

The serious health implications of obesity include comorbidities such as a range of cardiovascular diseases, type 2 diabetes, musculoskeletal disorders, and some forms of cancer. Obesity significantly increases, in some cases doubling, an individuals lifetime risk of developing all of the aforementioned conditions.

Obesity among American children has risen dramatically in the last decade, with a prevalence of more than 17%. The associated comorbidities of childhood obesity are no less serious than in the adult form and include insulin resistance, type 2 diabetes, high blood pressure, high total cholesterol, high LDL cholesterol, high triglycerides, sleep apnea, early puberty, orthopedic problems, various psychological symptoms (for example depression, eating disorders, poor self esteem), and poor body image. Furthermore, individuals who are obese as children are more likely to be obese as adults.

Obesity is known to run in families, but despite considerable effort, only a few common genetic variants have been identified that increase the risk of becoming obese. These include the FTO gene on chromosome 16.

The deCODEme Genetic Scan identifies variants in the FTO gene in customers of European descent and provides interpretation of their associated risk for the development of obesity. Current data shows no association between the variants in the FTO gene and obesity in other ethnicities and therefore further research is needed in order to elucidate its role.

risk factors

Risk factors for developing obesity include:

• Childhood obesity: Obesity in children and adolescents often continues into adulthood.
• Being overweight: Overweight is defined as a BMI greater than 25 but less than 30 kg/m². Being overweight can eventually lead to obesity.
• Excessive caloric intake: Increased caloric intake, especially in the form of saturated fats and simple sugars, increases the risk of becoming obese.
• Sedentary lifestyle: A sedentary lifestyle and general lack of physical activity increases the likelihood of becoming obese.
• Ethnicity: Hispanic and African Americans are at greatest risk, followed by individuals of European and Asian descent.
• Genetics: Twin and adoption studies have shown that genetic factors play an important role in obesity. Large groups of individuals have been evaluated for genetic variation related to the development of obesity. The genetic variations identified can be divided into 2 main groups: 1) rare forms that explain only a small fraction of the obese population, and 2) common forms that are present in a larger proportion of the obese population.

more information

You can find out more information about obesity by talking with your doctor and visiting these Web sites:

American Diabetes Association
American Heart Association
American Obesity Association
Centers for Disease Control and Prevention
Obesity in America
Weight-Control Information Network