Theoretical Framework for Dealing with Obesity

by | Jan 11, 2016 | 2010, Obesity, Weight Control

Written by Chrystal Moulton, Staff Writer. Review explores various factors influencing obesity.

Obesity is a multilayered problem affecting millions of people worldwide. However, no established approach has been affective in reducing the occurrence of obesity. In the current review(1), authors identified that obesity should be regarded as only a sign of excess caloric retention (or increased storage of energy as fat) and that clinicians should therefore seek the root causes or reasons leading to excess fat storage in these particular individuals.

The usual approach to induce weight-loss in overweight or obese persons is the eat less and exercise. In most cases, individuals that follow their prescribed plans experience weight loss. Nevertheless, about 66% of these regain the weight after 1 year and all of them after 5 years.(2) The authors believe these disappointing results occur because dietary plans are not being made to address root causes of overeating, which are affected by various socio-cultural, physiological, psychological, and medicinal factors. Obesity is simply caused by an imbalance of energy input (eating), metabolism (the body’s use and storage of energy), and energy expenditure (physical activity). Determining how these factors affect energy input, metabolism and energy expenditure is key to finding the right plan for overweight/obese patients.

Metabolic Rate
Individuals with low metabolic rate are more likely to be obese than those with a high metabolic rate. What this means is how much energy you body uses while at rest. This is usually referred to as basal metabolism or resting metabolic rate. Some factors that have been shown to affect resting metabolic rate include:

  •  Genetics- approximately 45-75% of individual differences in body mass is determined by our genes. In other words, some individuals are predisposed to obesity due to genes which code for a low metabolic rate.(3,4) Careful assessment of family history together with other health related factors can reveal any genetic risks related to obesity. Research in this area is still being developed.
  • Sex- women with the same body mass index (BMI) as men have about 20% lower metabolic rate as their male counterparts. Research shows this may be due to higher muscle mass in men compared to women.(5)
  • Aging- obvious declines in functioning naturally occur as we age—resting metabolic rate is no exception. As adults, we need to consume 150 calories less every 10 years to maintain a healthy body weight.(6)
  • Hormones- hormones that affect energy metabolism include cortisol, testosterone, and growth hormone (GH). Growth hormone is linked to decreases in metabolic rate and increases in fat mass. (7) Testosterone deficiency reduces metabolic rate and affects the building of muscle tissue.(8) Excess cortisol can break down muscle tissue and increase fat storage in the belly area.(9)
  • Loss of skeletal muscle- individuals with higher muscle mass have higher resting metabolic rate, and therefore changes in muscle mass affect resting metabolic rate. Obese individuals require more muscle to move the weight carried by the body, however inactivity affects muscle content in the body.(10) Sedentary people generally don’t have much muscle and therefore have a lower metabolic rate.(11) Also loss of skeletal muscle due to wasting may also affect metabolism.
  • Metabolically active fat- loss of brown adipose tissue, which accounts for 20% of resting energy expenditure, can contribute to a lower metabolic rate.(12) It is still unclear however, how much this plays a role in obesity.
  • Medications- beta-blockers such as …can reduce metabolic rate and promote weight gain.(13) Other drugs that increase metabolic rate include beta-adrenergic drugs (14) stimulants or performance enhancing drugs (15), coffee (16), and nicotine.(17) Discontinuing use of these drugs can result in weight gain.
  • Weight-loss- in some individuals weight loss of 5-10% corresponds to a 20% reduction in resting metabolic rate (18), making these individuals susceptible to weight regain.

Overeating
Eating accounts for 100% of our energy intake. For individuals struggling with obesity, overeating is a problem. However, the authors view it only as a symptom of an underlying root cause. These include:

  • Socio-cultural factors- individuals facing a lot of peer pressure, changes in job status (promotion from a laborious job to a desk job), and access to healthy foods (due to socioeconomic status) can play a role in obesity.(19) People who generally eat out with client or friends may unintentionally over eat due to differences in portion size from one eating place to another. The author describes this situation as “mindless eating.”(20) Identification of social pressures leading to overeating is a simple way to solve the problem in the individuals this mostly affects.
  • Physiological factors- defects in the body that affect hunger and appetite influence eating patterns. Authors broke it down into three aspects: genetic defects directly linked to any part of the biological system controlling hunger, which is generally rare (21); acquired defects due to brain injury or disease (22); and improper eating intervals, which is the most common problem. Skipping meals and eating late can lead to overeating in response to extreme hunger. Under this condition, individuals usually consume high carbohydrate energy dense meals, which in turn can lead to sharp spikes and fall in sugar levels and increase snacking behavior.(23) Furthermore, if the meals are not nutritionally balanced individuals may feel hunger even after the meal, in which case they eat again. Therefore, meal composition which affects satiety along with improper eating times, can lead to overeating and weight gain.(24,25)
  • Psychological factors- some people eat as a coping mechanism to deal with negative emotions including stress, sadness, anger, loneliness, anxiety, and frustration.(26) Psychiatric conditions such as depression, post-traumatic stress disorder, cognitive disorders, addictions, anxiety disorders, and sleep disorders can lead to overeating. Individuals with these conditions self-medicate with food.(27)
  • Medications and drug abuse- medications such as anti-diabetic agents, anti-depressants, anti-psychotic drugs, anti-convulsants, and hormonal drugs can promote hunger and appetite.(28) Also, recreational drugs such as marijuana and alcohol can increase appetite.(29, 30)

Physical Activity
Lack of physical activity is an obvious reason for weight gain. In sedentary individuals, the majority of their movements are a result of everyday activities such as walking, sitting, standing, and fidgeting. Reduction in these activities could influence weight gain.(31, 32) Barriers to increased physical activity can result from various factors similar to factors affecting eating behavior. This includes:

  • Socio-cultural factors- socio-cultural factors affecting the neighborhoods where individuals live can either induce or reduce physical activity. For example, if neighborhood is not perceived as safe, people will most likely stay at home. Also, access to public transportation, parks, and other recreational environments can be limiting factors. Furthermore, cultural beliefs that limit activity of certain individuals, pregnancy, citizenship status (immigrant or migrant), and other constraints can pose social pressures on individuals that promote inactivity and therefore, weight gain.(1, 33) Addressing social issues can encourage physical activity.
  • Medical factors- chronic muscular pain, osteoarthritis, respiratory conditions, and fibromyalgia can cause inactivity and thus could promote weight gain.(34) Addressing these issues first can initiate a plan individuals can stick to and promote weight loss and healthy living.
  • Psychological factors- depression is normally associated with low-energy levels, lack of motivation and lack of interest in exercise.(35) Also social anxiety disorder, phobias, and sleep disorders can affect one’s level of physical activity and promote weight.(36) Identifying and dealing with psychological disorders would be a first step to aiding in increasing activity.
  • Medications- there is not much research in the area of how drugs affect physical activity, however, drugs that reduce energy levels and induce drowsiness could likely play a role in obesity, especially in individuals who take such medications regularly.(1)

Overall, the authors encourage the view of obesity as “a clinical sign of chronic caloric retention [which] requires a systematic assessment of factors potentially affecting energy intake and expenditure.”(1)  The authors believe that addressing the underlying issues affecting metabolic rate, energy intake (eating), and physical activity could significantly alleviate the problem of obesity. By addressing the root causes clinicians can create a plan their obese patients can follow long-term and thus, improve general outcomes in the treatment of obesity. Furthermore, recognition of the causes and barriers will also help set realistic goals for patients to achieve and encourages life-long health.

Source: Sharma, Arya M., and Raj Padwal. “Obesity is a sign–over‐eating is a symptom: an aetiological framework for the assessment and management of obesity.” Obesity reviews 11.5 (2010): 362-370.

© 2009 The Authors

Posted on May 22, 2014.

Chrystal Moulton BA, PMP, is a 2008 graduate of the University of Illinois at Chicago. She graduated with a bachelor’s in psychology with a focus on premedical studies and is a licensed project manager. She currently resides in Indianapolis, IN.

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