Over 60 million U.S. adults, ages 20 years and older, are considered obese. The percentage of young people who are overweight has more than tripled since 1980. According to Center for Disease Control (CDC), a total of approximately 40 million American adults met the classification of obesity.
Obesity affects college students as much as the older adult population. The CDC states that in 2000, 15.2 million college students are obese. This was up almost 8% from 1991, in which obesity was only evident in 8% of college students.
Obesity is not the same as being overweight. The dreaded “Freshman 15” does not make you obese. The CDC defines obesity “as an excessively high amount of body fat or adipose tissue in relation to lean body mass. Body Mass Index (BMI) is a common measure expressing the relationship of weight-to-height. BMI is a mathematical formula in which a person’s body weight in kilograms is divided by the square of his or her height in meters (wt/(ht)2). Individuals with a BMI of 30 or more are considered obese.”
Obesity has a profound effect on public health and the economy. It accounts for $93 billion per year in health expenditures, not counting the cost of lost productivity. Currently, about 32 percent of Americans are obese, the highest level in the world. As with any other disease, millions of dollars are being poured into the search for a cure.
These rates raise concern because of their implications for Americans’ health. Being obese increases the risk of many diseases and health conditions, including the following:
Obesity increases blood pressure. Hypertension that is untreated can increase the risk for heart failure, kidney failure, and stroke.
Obesity can cause high total cholesterol or high levels of triglycerides
In the U.S. there are 15 to 16 million adults who have diabetes, of these, 90 to 95% are classified as diabetes mellitus type II (DM type II), the type associated with obesity. About 80 to 90% of persons with type II diabetes mellitus are obese. About two-thirds of persons with DM type II have a BMI of at least 27, and half of persons with DM type II have a BMI of at least 30. The prevalence of DM type II in the U.S. increased by 25% in the last decade.
Obesity and hyperglycemia increases the risk for coronary artery disease, leading to myocardial ischemia and myocardial infarction. Even obese persons who do not have hyperglycemia can have an increased risk for coronary atherosclerosis. Atherosclerosis is potentially reversible by adopting major lifestyle changes.
The rate of ischemic cerebrovascular disease is higher for the obese.
Biliary tract lithiasis, manifested mainly by development of cholelithiasis (gallstones), is more likely to occur in persons who are obese. The gallstones are typically of the mixed type with cholesterol. Cholelithiasis can lead to cholecystitis and to pancreatitis.
Increased weight increases the stress on weight-bearing joints, particularly lower extremities, leading to osteoarthritis. A BMI of 30 or more increases the risk for osteoarthritis of the knees.
Persons who are obese have a greater likelihood for sleep apnea. Persons who snore have a propensity to develop sleep apnea. The increased soft tissue in upper airways contributes to the problem. Sleep apnea is accompanied by decreased ventilation (hypoventilation) and pulmonary dysfunction. Persons with a BMI of 30 or more are at greatest risk for obesity hypoventilation syndrome, particularly persons who carry their excess weight in their abdomen
The death rates from all cancers are greater for persons who are obese. The range of cancer types is broad, including esophagus, colon, rectum, liver, gallbladder, pancreas, kidney, non-Hodgkin lymphoma, prostate, stomach, and multiple myeloma. Obesity increases the rates of breast, uterine, cervical, and ovarian cancers.
Metabolic syndrome shares common features with diabetes. Metabolic syndrome is also known as Syndrome X, or insulin resistance. It involves a BMI over 30, high cholesterol, and hypertension.
Some obese patients who have little or no coronary artery disease and do not have a history of hypertension may still develop heart failure. In these patients, the heart is globally enlarged, similar to a dilated cardiomyopathy. If weight is lost, the heart shrinks in size. This obesity cardiomyopathy may be related to blood volume expansion or other factors.
NAFL is being seen more frequently. Dietary patterns play a role in the development of steatosis (fatty change) in the liver.NAFL reduces the metabolic function of the liver. NAFL can proceed to non-alcoholic steatohepatitis (NASH), to liver failure, and even cirrhosis, with an increased risk for development of cancer.
Women who are obese are more likely to have menstrual irregularities and ovulatory infertility, including the polycystic ovarian syndrome (PCOS). Women with PCOS typically have irregular bleeding, hirsutism, and/or infertility. Weight loss can aid in treatment of PCOS. Obesity in women who are pregnant increases the likelihood for gestational diabetes that can affect the developing fetus. Maternal obesity increases the risk for neural tube defects in the fetus.
Recent research has also shown that the obese are ostracized, isolated, and often treated differently than their “normal” weight peers. This negative social feedback – whether real or imagined – is often internalized. This can lead to alcohol and drug use, failure in school, depression, eating disorders, distorted body image, and low self esteem. These feelings and behaviors can have long-term repercussions.