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Obesity Causes


According to the Centers for Disease Control and Prevention (CDC), approximately 9 million adult Americans are morbidly obese. This is 4.7 percent of the U.S. population, up from 2.9 percent in 1994. The severity and prevalence of this problem make morbid obesity a very serious national health crisis.

Caloric Intake

The causes of obesity cannot be defined easily. An individual's transition from normal weight to overweight to obesity to morbid obesity usually involves an intake of food calories that is greater than the rate at which the individual is burning off those calories. However, there are many different reasons for this imbalance of calories in/calories out, and several factors are involved. The causes of obesity may include an individual's genetic makeup, metabolism, culture, environment, socioeconomic status, and behavior. Treatment options for obesity may include bariatric surgery such as gastric banding or gastric bypass surgery.

Genetic Factors

It is possible for an individual's genetic makeup to directly cause obesity; disorders such as Prader-Willi syndrome and Bardet-Biedl syndrome are examples. However, most cases of morbid obesity are not based solely on such a genetic cause. The term "genetic factors" might be more easily understood as "heredity." It has been observed that obesity often runs in families, with obesity being more common in some families than others. This would suggest genetic causes of obesity. However, a given family would also probably share a similar lifestyle and similar diet, which would contribute to the incidence (or absence) of obesity.

There does appear to be at least an association between heredity and obesity. In a well-known study regarding this issue, adults who were adopted as children were found to have body weights closer to those of their biological parents than their adoptive parents, suggesting that their genetic makeup had more influence on their body weight (and the incidence of obesity) compared to the environment in their adoptive family's home.

In another frequently cited study, it was noted that identical twins, even when raised apart from one another, had similar weights much more frequently than did fraternal twins. In other words, the identical twins (who shared DNA and genes) showed much more similar weight patterns than their non-DNA-sharing counterparts.

Environmental Factors

A person's environment (at home, work, school, at play, in the community, etc.) can have a significant impact on his or her risk of developing morbid obesity. His or her "environment" in this regard would be comprised of:

  • The types of food that are available to the individual
  • The quantity of food available
  • The level of physical activity available or attainable
  • The diet and exercise habits of the individual
  • Diet and exercise habits of people in the individual's immediate environment

People may make health-related lifestyle decisions based on their environment. For example, someone may choose not to walk to many places because of the car-oriented layout of the surrounding community. Another individual might find the unhealthy lunch buffet at his/her office very difficult to resist. And of course, children do not have much control over their environment; their food choices are usually dictated by their parents.

Psychological Factors

A person's risk of developing morbid obesity is often heavily influenced by psychological factors. Boredom, depression, anxiety, stress, trauma (whether as an adult or child), and feelings of low self-esteem are examples of psychological factors that could result in an individual's overeating and under-exercising. Although the psychological aspect of morbid obesity can be difficult to overcome, it is not impossible. Merely identifying the psychological problems can help an individual greatly in his or her understanding of the basis of overeating.

Other Causes of Obesity

Illnesses can also lead to morbid obesity. Some of these include hypothyroidism, Cushing's syndrome, depression, and other neurological problems. The use of steroids and certain antidepressants can also lead to weight gain.

Consult a Bariatric Surgeon about Treatment

Morbid obesity surgery is an increasingly common procedure used to treat individuals with morbid obesity. However, the varying causes of morbid obesity and the plethora of obesity problems further complicate the issue of whether obesity surgery is appropriate for a given individual. Speak to a local weight loss surgeon to find out if bariatric surgery is appropriate for you.

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