Causes of Severe Obesity

The reasons for obesity are multiple and complex. Gaining weight is a result of an energy imbalance. However, despite society's typical assumptions, it is not simply a result of overeating. Overweight and obesity can be impacted by genes, metabolism, behavior, environment, culture, and socioeconomic status. Additionally, many people experience weight gain and subsequent obesity as a result of environmental factors out of their control such as disease or even accidents.

Science continues to search for answers. Until the disease is better understood, the control of excess weight will continue to be a struggle for the entirety of a patient's life. That is why it is very important to understand that all current medical interventions, including weight loss surgery, should not be considered medical cures. Rather they are tools that attempt to reduce the effects of excessive weight gain and alleviate the serious physical, emotional and social consequences of the disease.

Contributing Factors:

Genetic Factors

Numerous scientific studies have established that your genes play an important role in your tendency to gain excess weight.

  • The body weight of adopted children shows no correlation with the body weight of their adoptive parents, who feed them and teach them how to eat. Their weight does have an 80% correlation with their genetic parents, whom they have never met.

  • Identical twins, with the same genes, show a much higher similarity of body weights than do fraternal twins, who have different genes.

  • Certain groups of people, such as the Pima Indian tribe in Arizona, have a very high incidence of severe obesity. They also have significantly higher rates of diabetes and heart disease than other ethnic groups.

We have a number of genes that influence our body's weight. Just as some genes determine eye color or height, others affect our appetite, our ability to feel full or satisfied, our metabolism, our fat-storing ability, even our natural activity levels. These can play a significant role in your ability to lose and maintain a healthy weight. Research has shown that in many cases once the problem is established, efforts such as dieting and exercise programs have a limited ability to provide effective long-term relief.

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Environmental Factors

Environment is one of the best areas for prevention and treatment of obesity. People make a lot of decisions based on their environment and community. One may choose to eat out more often as the grocery store is further than the restaurant. They may drive to work because the weather isn't pleasant. Or they may choose high calorie snacks because they are always available at work.

If you have a genetic predisposition toward obesity then the modern American lifestyle may make controlling your weight more difficult. We are eating out more than ever and even those eating at home are choosing more convenience foods or pre-prepared foods. Additionally, we are much less active. Our fast-paced lifestyle has allowed us to accomplish more with less effort. Most do not meet the current recommendations of 1 hour or more of activity a day.

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We used to think of weight gain or loss only as a function of calories ingested and then burned: take in more than you burn, gain weight; burn more than you ingest, lose weight. But we now know that the equation isn't so simple.

Obesity researchers…. Where the calories come from is also being studied. It seems that nutritional balance may play a more significant role in weight loss than was originally thought - all your calories from carbohydrate may not be as useful as a balance of nutrients.

What this means is that we need to 'trigger' the metabolism in any way we can to help lose the weight and then maintain. There are a few factors that are diet and behavior related that can help: exercise, meal pattern, dietary balance and hydration.

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As our society has become bigger and busier our eating habits have fallen on the priority list. This has enabled us to form bad eating behaviors. These can affect your weight almost as significantly as the calorie intake. One obese patient may be hungry all day and eat 6 times. Another may never be hungry and only eat once. Calories may differ significantly but both people struggle with obesity. Making behavioral changes can sometimes be some of the most difficult because they are often influenced by both genetics and environmental factors.

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Eating Disorders & Medical Conditions

Weight loss surgery is not a cure for eating disorders/disordered eating. Sixty percent of individuals seeking treatment for obesity have some kind of eating disorder according to a 2007 Harvard study. These patients already have an unhealthy relationship with food and their bodies. They are often the ones most at risk for developing or experiencing a recurrence of disordered eating after surgery. Disordered eating does not disqualify a patient from bariatric surgery. However, they are typically referred for counseling to help them cope before, during the process and after surgery with all the lifestyle, dietary and emotional changes.

There are a number of medical conditions, such as hypothyroidism, that can also cause weight gain. Certain medications used for health problems may also result in weight gain. That is why it is important that you work with our doctor to make sure that you do not have a condition that should be treated with medication and/or counseling prior to proceeding with weight loss surgery.

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