The reasons for obesity are multiple and complex — it is not simply a result of overeating. Several factors such as a person's genes, metabolism, behavior, culture and socioeconomic status can contribute to obesity. 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 obesity is better understood, many people will struggle to maintain a healthy weight throughout their lives. That is why it is very important to understand that all current medical interventions, including weight loss surgery, should not be considered cures for obesity. Rather they are tools that can help to reduce the effects of excessive weight gain and alleviate the serious physical, emotional and social consequences of obesity.
Numerous scientific studies have established that your genes play an important role in your tendency to gain excess weight. For example, the body weight of adopted children does not correlate with the body weight of their adoptive parents, who feed them and teach them how to eat. However, the body weight of these children does correlate 80 percent with their biological parents, whom they have never met. Identical twins, who have the same genetic makeup, show much higher similarity in body weight than 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 and even our natural activity levels. These genes can play a significant role in your ability to maintain a healthy weight. Research has shown that in many cases dieting and exercise programs have a limited ability to provide effective long-term relief.
Environment is one of the ideal areas for prevention and treatment of obesity. People make a lot of decisions based on their environment and community. For example, a person may choose to eat out more often if the grocery store is farther away than the restaurant. Someone may drive to work instead of biking or walking if the weather isn't pleasant. People 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 eat out more than ever and even those eating at home often choose convenience foods like frozen dinners that typically contain high amounts of sugar, fat and sodium. Additionally, we are much less active than we used to be. Our fast-paced lifestyle has allowed us to accomplish more with less effort. Most people do not meet the current recommendations of one hour or more of physical activity a day.
Scientists used to think of weight gain or loss only as a function of calories ingested and then burned. If you took in more than you burned, you gained weight. If you burned more than you ingested, you lost weight. But it turns out the equation isn't so simple. Scientists are now studying how a calorie's source affects weight. It seems that nutritional balance may play a more significant role in weight loss than was originally thought. For example, if all of your calories come from carbohydrates you may find it hard to maintain a healthy weight and get necessary nutrients. What this means is that we need to trigger the metabolism in order to lose weight and then maintain a healthy weight. Exercise, meal patterns, dietary balance and hydration are all tools than can help regulate the metabolism.
Unhealthy eating behaviors can affect your weight almost as significantly as calorie intake. For example, one obese patient may be hungry all day and eat six times while another may never feel hungry and only eat once. Though their calorie intake differs significantly, both people struggle with obesity. Making behavioral changes can be difficult because these habits are often influenced by both genetic and environmental factors.
Weight loss surgery is not a cure for eating disorders or disordered eating (abnormal eating behaviors). 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. 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, patients who struggle with disordered eating are typically referred for counseling to help them cope with the lifestyle, dietary and emotional changes associated with surgery.
In addition to disordered eating, there are a number of medical conditions, such as hypothyroidism, and certain medications that cause weight gain. It's important to ensure you do not have a condition that should be treated with medication or counseling prior to proceeding with weight loss surgery.