The Correlation Between Obesity, Depression, and Physical Activity

Obesity is becoming an impending epidemic in our society (Hill, Wyatt, Reed, & Peters, 2003; Kottke, Wu, & Hoffman, 2003). Prevalence of obesity is on the rise and deaths attributable to it are higher than ever. It is estimated by the NIDDK (2003) that 30.5% of adults in the United States are obese and if the rate of increase remains constant, 39% of adults will be obese by the year 2008 (Hill, et al. 2003). In a study conducted by Thorpe, et al. (2004) out of 2681 New York elementary school students 24% were obese, so there is a high prevalence in children as well. Flegal, Williamson, Pamuk, and Rosenberg (2004) discovered that the obese population contributes ten times more deaths per year, about 300,000, than the portion of the country within normal weight categories.

The cost of lives is not the only payment for obesity, the nation suffers economically as well by paying more for health care (Kottke, et al. 2003). Obese medical patients have many more risks associated with medical care (NIDDK, 2003; Neville, Brown, Weng, Demetriades, & Velmahos, 2004). A higher rate of multiple organ failure is prevalent in the obese which often leads to death (Neville, et al. 2004). This means that obese patients need to be monitored more closely, which effectively costs more (Neville, et al. 2004). There are also indirect costs of obesity due to lost jobs by individuals who are disabled by their condition (Kottke, et al. 2003). Overall, the yearly cost due to obesity is estimated to be 117 billion dollars (NIDDK, 2003).

The words obesity and overweight can have a broad meaning. Scientists and physicians, however, have designated a small number of accepted systems associated with body mass index, or BMI. BMI is a measurement of height versus weight, and appears in the units kg/m^2 (Ariza, Greenberg, & Unger, 2004; NIDDK, 2003). Most research is done with the guidelines being a BMI of 25 to 29.9 is considered overweight, and a BMI greater than 30 is considered obese. There are even higher categories where a BMI greater than 40 is considered severely obese.

The reason obesity is so awful is because there are serious health risks associated with this problem (Grundy, et al. 1999; NIDDK, 2003; Veronelli, et al. 2004). Some of the major comorbities of obesity include coronary artery disease, diabetes, hypertension, and osteoarthritis (Grundy, et al. 1999; NIDDK, 2003; Veronelli, et al. 2004).

Television, videogames, the internet, high fat low-cost food, low physical activity level, and a low level of education puts society at risk for obesity because all of these factors combine to make a inactive lifestyle. According to Cottam (2004) this utilitarian lifestyle, the pleasure first attitude predisposes people to becoming obese. Lack of education is a large determinant in having a predisposition to obesity as well.

Although many people are predisposed to being obese society has the ability to take back the control and adopt a healthier lifestyle. This control would effectively be regained by targeting the population of children (Fowler-Brown & Kahwati, 2004). Childhood is the most critical time to prevent a person from becoming obese, because between the ages of four and six children go through adiposity rebound (AR) (Ariza, et al. 2004). AR is where the adiposity in a child significantly increases (Ariza, et al. 2004). The adipose tissue developed during this time period will have to be fed for a lifetime (Ariza, et al. 2004). And according to Ariza, et al. (2004) the heavier a child is at adiposity rebound, the more likely they will grow up to be an obese adult.

The initiative taken to prevent the childhood population from becoming obese rests squarely on the shoulders of physicians and parents (Fowler-Brown & Kahwati, 2004; Gill, MacDougall, & Taylor, 2004). It is the physician's role to educate the parents about how to prevent obesity in their child (Kottke, et al. 2003). Education of the parent is important, because if the parent believes that their child is leading a healthy lifestyle then they are less likely to interject and make a change in the child's everyday habits (Gill, et al. 2004; Grundy, et al. 1999; Hill, 2004).

When considering children, weight maintenance is often enough to treat childhood obesity because BMI will decrease over time as they grow (Fowler-Brown & Kahwati, 2004). For adults and children, however, an effective way to lose weight is to decrease the amount of energy taken in and to increase the amount of energy expended (Grundy, et al. 1999). This means eating less food and being more physically active, because a positive energy balance is the cause of obesity (Grundy, et al. 1999). Physical activity increase alone can change the energy balance and the body of an obese person (Grundy, et al. 1999). This causes changes such as lowering the white blood cell count of the body which lowers the risk of developing atherosclerosis (Veronelli, et al. 2004). Lowering white blood cell count by losing weight also lowers the risk of cardiovascular disease (Veronelli, et al. 2004).

The effects of physical activity on obesity are well documented, but there are other psychosocial factors that feed into being obese. Obese people are often teased, ridiculed and physically abused throughout their life. This can lead to depression and low self-esteem (Dixon, Dixon, and O'Brien, 2003) conducted studies that agreed with the notion that obesity causes depression and that obese women are at a higher risk to be depressed than men.

According to Fowler-Brown & Kahwati, (2004), those who are depressed are more likely to develop a sedentary lifestyle, while Hill, et al. (2004) confirmed that obesity is a result of physical inactivity. Feeding into and completing this cycle Dixon, et al. (2003) stated that obesity is a cause of depression. Obese persons have a feeling of hopelessness and a low self esteem which causes them to be less physically active because they may see exercise as another place where they will fail (Artal, Sherman, & DiNubile, 1998).

Physical activity has the ability to treat mild to moderate symptoms of depression, however, major depressive symptoms should be treated with drug therapy and psycho therapy (Artal, et al. 1998; Fontaine, 2000). Although the mechanistic relationship between depression and physical activity is not known, exercise can give a depressed person a feeling of accomplishment and a sense that they have taken some control back in their lives (Artal, et al. 1998). Intense sessions of physical activity also causes the release of Beta-endorphins which reduces pain and produces a relaxed feeling, which can ease the symptoms of depression (Artal, et al. 1998). The most important concept according to Osness and Mulligan (1998), however, is that short bouts of physical activity is not what is required to