Causes of Obesity and Weight Gain

Obesity has been poorly labeled as a cosmetic issue in American perception. Weight gain and obesity account for increased health costs, discrimination lawsuits and decreased productivity but the causes of obesity are not clear. Awareness by researchers and public health officials shed light on the tremendous health consequences of obesity. Obesity and morbid obesity are now considered a public health crisis, clearly changing the definition of obesity.


No simplistic answers about obesity exist. Weight gain and loss depends on a number of factors. Here we'll detail some of the more common causes of obesity.

Obesity tends to run in families, implying genetic factors. The search for an "obesity gene" is complicated, however, by the fact that families also tend to share eating and lifestyle habits, making it difficult to separate genetics per se from behavior. Studies have been designed to determine how significantly genes and family lifestyles affect obesity.

Recent studies acknowledge a condition known as metabolic syndrome that has the potential for defining a cause of obesity. The premise of the metabolic syndrome, according to researcher Richard P. Lifton, is that clusters of illnesses like high cholesterol and high blood pressure may be directly related to gene mutations in the mitochondria or energy center of the cell. It is yet to be determined if weight gain triggers metabolic syndrome or if metabolic syndrome triggers weight gain.

The average American is inundated with fast food, processed food, and enriched food choices on a daily basis. Advertisements for these food products boast their nutrition values and ease of preparation can make our lives easier. We lead busy lives, eat fast, and choose television or computer over exercise. At the same time, underweight models on our magazines and movie screens symbolize a distorted American ideal.

The point's been hammered into us with such frequency that we hardly hear it anymore: in cultures where people eat high fat diets and get little exercise, more problems with weight gain are seen than in groups who eat low fat diets and get regular exercise. America falls squarely into the high fat/low exercise category. This is unlikely to change quickly, so anyone trying to lose weight has to contend with a culture that marginalizes the obese while simultaneously creating the perfect environment for weight gain. Trying to deal with this contradiction may be one of the leading psychological causes of obesity as well as eating disorders.

It's no surprise that psychological factors and behavioral problems may cause weight gain in people. Many people eat when they're stressed, bored or angry. Over time, the association between an emotion and food can become firmly fixed.

Depression and stress are leading causes of obesity and eating disorders. Indeed, obesity can be traced to behavioral or psychological difficulties. Contrary to popular myth, this does not indicate weakness or lack of will power. A mental disorder is as much a disease as any physical problem, and requires professional treatment.

Certain physical disorders can lead to overeating, or interfere with the body's mechanism that regulates calorie use. Neurological damage can also interfere with proper calorie intake, especially if the hypothalamus, which regulates appetite, is damaged. In Cushings Syndrome, increased levels of cortisol are secreted. Cortisol, also known as the stress hormone, is known to increase the appetite, which may be a cause of obesity.

Physical causes of obesity should always be considered. A condition known as hypothyroidism can lead to weight gain. In fact, hypothyroidism, a condition of the thyroid that slows the body's metabolism way down, is one of the significant causes of obesity in adults and in children.

Research is slowly revealing how hormones play a role in obesity. When full, fat cells release the hormone leptin, which curbs appetite. If leptin production is hindered, the fat cells are unable to signal that they're full, and weight gain occurs.

Certain medications can also be a cause of obesity. Steroid medications are common culprits increasing the amount of fluid the body holds in the body. Some migraine medications are also known to cause weight gain. Antidepressants and other mood altering medications, sometimes used for the treatment of stress, anxiety and depression can also cause increased weight gain.

 

Centers for Disease Control and Prevention (CDC). (updated 2004). Defining overweight and obesity.

Haggerty, M. (1999). Obesity. Gale Encyclopedia of Medicine.

National Institute of Diabetes and Digestive and Kidney Diseases—Weight-Control Information Network. (2001, October). Understanding adult obesity [NIH Publication No.01-3680].

National Library of Medicine. (updated 2001). Morbid obesity. MedlinePlus Medical Encyclopedia.