Since the mid-seventies, the prevalence of overweight and obesity in the United States has increased sharply for both adults and children. Data from two NHANES surveys show that among adults aged 20-74 years the prevalence of obesity increased from 15.0% (in the 1976-1980 survey) to 32.9% (CDC, 2005). Between 25% and 30% of young children and between 18% and 25% of adolescents in the US are overweight. This trend is a great concern, because overweight is associated with increased risk for health problems, such as diabetes, gallbladder disease, and sleep apnea. In addition, overweight in childhood is associated with overweight in adulthood, and overweight adults have increased risk for conditions, such as heart disease, high blood pressure, and certain cancers.
Definition of overweight and obesity
The measure of overweight is Body Mass Index (BMI). It is calculated by dividing weight in kilograms by height in meters squared and expressed in kilograms per meter square. The BMI for age is correlated with total body fat content. Because BMI changes as children get older, BMI for age is the measure used for individuals over 2 years of age. Overweight in children and adolescents is determined by using Body Mass Index (BMI). Children and adolescents at risk for overweight have BMI at or over the sex-specific 85th percentile, and those with BMI at or above the 95th percentile are classified as overweight. For example, a 7-year-old girl whose weigh is 90 pounds (40.93 kg) and height is 52 inches (1.32 m) will have a BMI of 23.54, which is over the 90th percentile when plotted on the BMI chart for girls 2 -20 years of age. Therefore, this girl is overweight. For adults, a BMI above the 85th percentile signifies overweight and above the 95th percentile obesity. The BMI increases rapidly from birth to about 8 months of age, then decreases until approximately age 6 years. At that point, it reaches its lowest point before increasing again. This phenomenon is called adiposity rebound. Studies show that there is a correlation between a younger age of adiposity rebound and a higher body fat content at an older age.
Trends in overweight
According to the Center for Disease Control, overweight occurrence among children and adolescents was stable from 1960s to 1980. However, it almost doubled between 1976-1980 and is still rising.
The prevalence in children and adolescents is greatest for Mexican boys and black, non-Hispanic girls.
Health, emotional, and economic costs related to being over weight
Overweight has been associated with a number of health problems, such as high blood pressure, heart and gallbladder disease, sleep apnea, diabetes, as well as some cancers. In addition, affects mental health of children and adolescents. Over weight people report negative assumptions made about them by others, including being lazy, strong, and tougher than others, not having feelings, and being unclean. Because of the negative implication, heavy individuals tend to develop negative self-image. There are 300,000 annual premature deaths directly related to it and its consequences in the United States.
Overweight-associated annual hospital cost (based on 2001 constant US dollar value) increased more than threefold, from $ 35 million (0.43% of total hospital costs) during 1979-1981 to $ 127 million (1.70% of total hospital costs) during 1997-1999 . Unfortunately, treatment for overweight in adulthood may not be very effective, as most participants in weight loss programs gain back all of their weight within 5 years. There is some evidence that children respond better to treatment than adults. Therefore, interventions to treat this condition should start in childhood. Ultimately, steps should be taken to prevent childhood and adolescent weight problems altogether. I said it before, and I will say it again: prevention is the best medicine.