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Chapter 3

A Complex Mix of Factors

Physiological Factors

There are many causes for excess weight. However, genetic makeup clearly contributes to the tendency to gain weight. The gene pool influences body shape, adiposity, and susceptibility to disease. In Maffeis’ (2000) review of the literature, he reports that inheritance is responsible for 25–40% of the interindividual differences in adiposity. In 2005, Lyon and Hirschhorn estimated that 30–70% of the variation in obesity within a given population is the result of heredity (Lyon 2005). In most cases, environment greatly influences the expression of genetic material, making parental obesity an important risk factor for obesity in children. Of those who become obese as adolescents, 70% grow up to become obese adults (Zhao 2011). Science is working to uncover the many physiological pathways that influence body weight and to identify ways to interrupt or influence those biological pathways (Zhao 2009).

Medications can also contribute to weight gain. For example, steroids and most antidepressants stimulate hunger. Though such medications are helpful to treat the condition for which they are prescribed, it seems only fair that these side effects be explained and discussed, especially with the patient who is already overweight, before prescribing them.

Changing lifestyle can modify inherited risks, but to what extent? Patients come from different genetic backgrounds and have to play the hand that they are dealt. Therefore, the care providers may find it difficult to assess or appreciate the strength of the biological forces pulling someone toward food. Notice how patients describe their experience with a food-related problem. It is in this context that they must solve problems.

Over time, science will create more effective treatments for obesity, but lifestyle modification will continue to provide the greatest influence on both health and body weight. Lifestyle refers to the myriad choices that individuals make; those decisions that reflect their personal preferences and shape their daily routines. Lifestyle includes what, where, when, and how much one eats, what clothes the individual chooses to wear, the environment in which one lives and works, social relationships (e.g., family, work, friends), and personal hobbies. Most groups consider our modern lifestyle, particularly sedentary lifestyle and the influence of westernization, to be the cause of worldwide increases in overweight and obesity over the last few decades (WHO 2000).

With high-caloric food, large portions, and snack foods readily available, daily energy intake easily exceeds expenditure. The same genotype expresses itself differently in a hunter-gatherer society than in our society of computers and fast food. In 2011, the mismatch of our biological makeup and our convenience-driven environment has created a problem to solve. Part of the solution will be to redesign our environment.

Environmental Factors

Society has created an environment that nurtures obesity. Weight gain is a natural byproduct of modern convenience. There are countless culprits in our modern world: large food portions, desk jobs, remote controls, computer games, machines that do physical work for us, urban sprawl, snack dispensers, elevators, hard-to-find staircases, car culture, clever commercials, fast food, frozen meals, and so on. Individually, any single one of these isn’t going to make a population overweight, but when combined, these conveniences have reduced the activity levels and increased the caloric intake of an unsuspecting public.

Several new collaborations of local communities, private industry, service organizations, and national government are working to create environments that support physical activity and healthy eating. Resources for individuals and groups of all ages include: the President’s Council on Fitness, Sports & Nutrition (www.fitness.gov); Let’s Move! (www.letsmove.gov); Shaping America’s Youth (www.shapingamericasyouth.org); Small Steps (www.smallstep.gov); Healthy Kids, Healthy Communities (www.healthykidshealthycommunities.org); and a number of state-specific plans.

It is possible to plan environments in which residents can increase activity without thinking about it too much. Environments that support activity could include safe parks and biking trails near homes, building layouts that encourage the use of stairs, and walking (or pedestrian) malls. Several organizations and numerous websites offer information about how to build communities that encourage walking and biking. Among them are the Partnership for a Walkable America (PWA) (www.walkableamerica.org), the Pedestrian and Bicycle Information Center (PBIC) (www.pedbikeinfo.org), and International Walk to School (www.iwalktoschool.org). Information alone will not guarantee behavior change, but by offering environmental support, communities can encourage healthy living by making better choices easier.

Modifying lifestyle is changing usual routines. Change requires time as well as effort. Specifically, to accomplish a lifestyle change, someone must make time for it in his or her usual schedule. Consider two women equally motivated to incorporate a 30-minute walking session three days a week into their lifestyles. The first woman drives to her gym for a 30-minute walk around an indoor track, a drive that takes 15 minutes each way. By the time she’s done, she’s spent at least 60 minutes on her “exercise session.” The second woman lives in a neighborhood where she can simply step out her front door and walk for 30 minutes. Which woman is more likely to stick with her exercise routine and actually increase the number of days she works out in the future?

Hill (2006) proposes that personal responsibility that can be supported by even small changes in the environment offers the most realistic hope for progress.

Lifestyle

Regardless of genetic background or the medical treatments used, lifestyle choices about food and activity influence body weight. There are multiple physiological pathways in the human species that influence energy balance, and there are even more behavior patterns that influence energy balance in individuals. To make the task of supporting lifestyle change even more difficult, the mechanisms that drive behavior patterns are often not evident and more or less invisible to the person with the behavior. We hope that the difficulty in facilitating behavior change will not dissuade us from pursuing it as a viable (and effective) treatment option. If someone enters a clinic with an infection, do we just treat it or do we look for what is causing the infection? We look for the source of the problem. It is at least as important to look for the source of problematic behavior patterns before considering treatment options.

There are many reasons that prompt people to eat more than they need. Eating more than the body requires is “excessive eating” whether the food portions are large or the caloric content is high. For most people, an appropriate intake at 20 years of age becomes excessive at 40 due to changes in physical activity. Today, hunger is rarely the only reason for eating. Frequently, people eat because they are prompted by habit, because they feel pressured by social circumstances, or because they use it as a way to cope with discomfort.

An iceberg is a useful metaphor to describe the factors that influence obesity (see Fig. 2, below). We often only interact with the tip of the obesity iceberg—its physical components. Below the waterline are the true obstacles, the behavioral and genetic factors that drive obesity. We are able to make effective, sustained change at the tip of this iceberg if we can trace and address the underlying factors. Health care providers have the opportunity to help patients identify, address, and change the behavioral patterns that encourage excessive eating. The following sections describe reasons obese people report for accumulating excess pounds.

Figure 2—The Iceberg

Food Habits

Daily food habits often contribute to excessive eating and obesity. Much like a person’s genetic makeup, dietary patterns can be passed on from one generation to the next. Children who grow up with high-fat meals, routine snacking in front of the TV, and a well-stocked cookie jar are likely to continue those habits in their own homes, thus perpetuating excess weight regardless of genetics. Habits such as skipping meals, eating while driving, eating take-out meals, and drinking high-calorie beverages can all easily develop in response to tight schedules, family demands, fatigue, poor planning, or social pressure. Awareness, information, and support can help committed individuals change these habits. However, cravings complicate this process.

Cravings

One of the most common weight-loss questions is why is it so hard to stick with healthy behaviors, even when we know exactly how to eat well and know when we make poor choices? Eating is often affiliated with feelings and needs rather than with what we know to be healthy habits. When excessive eating satisfies underlying needs, those needs must be addressed during weight-reduction treatment or they will obstruct weight loss and interfere with sustained efforts to lose weight.

Figure 3 organizes motives for excessive eating from the iceberg (Fig. 2), similar to Maslow’s motivational hierarchy of needs, where a need motivates behavior (Maslow 1968).

Figure 3—Excessive Eating and Maslow’s Motivational Hierarchy

Craving, which often leads to excessive eating, is associated with “faulty” hunger awareness, which arises from different biological and psychosocial needs. The biological function of eating—to provide energy for life—has changed. We expect food to satisfy other human needs. People eat to build a sense of security, affinity, or self-actualization. Thus, to alter the reasons for excessive eating, an obese or overweight person has to discover what function excessive eating serves. There may be a way to make these cravings unnecessary or to create a sense of satisfaction with something other than eating. Emotional reasons for cravings sometimes overlap. The following categories of cravings are arbitrary, but may be helpful in identifying possible sources of cravings. You can find practical approaches to helping the patient solve these issues in chapter 17.

Stress

Many people eat in response to stress. According to the psychological definition, stress arises from an imbalance between a person’s perceived resources and perceived demands (Lazarus 1984). People look for coping skills that help them adapt to and manage that imbalance and may respond to stress with active or passive coping strategies (de Ridder 1997).

Henry (1977) describes active, problem-focused coping as a “fight-or-flight” strategy and passive coping as a “defeat reaction” or loss of control. Eating for comfort is a passive coping strategy (Popkess-Vawter 1998). Reports suggest that these cravings are due to the energizing power of sweets and the calming effect of fats (Wells 1998). Some evidence points to a relationship between the passive coping style and obesity (Hörchner 2002) and with the release of the cortisol hormone (Bob 2008), which is associated with central obesity, type 2 diabetes, and other components of the metabolic syndrome (Ljung 2001, Phillips 2010).

Research shows that obese people use passive coping more often than active, problem-focused coping (Rydén 2003). Hunger has been associated with feelings of hopelessness (Chilton 2007). Eating may offer a way to escape problems that are perceived as too difficult or impossible to solve (Popkess-Vawter 1998). Obese women particularly describe eating as a way to feel better in stressful situations (Laitinen 2002). Due to the significant association between passive coping and central obesity, some researchers interpret abdominal fat as an indicator of hopelessness (Björntorp 1999).

Symptoms of stress can be physiological and psychological. If a person has coped with stress through excessive eating and then stops that eating without addressing the initiating stressors, other stress symptoms may emerge. Feelings of anger, irritation, isolation, and depression, along with impaired memory and concentration, sleep disturbance, palpitations of the heart, hypertension, and tensed muscles could be symptoms of stress overload.

Chronic stress affects the hippocampus, the brain structure that provides information on how the environment is organized (Sapolsky 1996). Thus, stress may fragment and distort a person’s assessment of their environment and impair their learning and memory (Ivy 2010). This phenomenon has many implications for health care providers. For example, receiving a diagnosis of diabetes or any other medical problem is usually traumatic and stressful. Initially, patients may have difficulty understanding and assimilating medical or dietary recommendations, because the world with which they must interact has become radically different. Some time and/or help to adjust to the diagnosis may reduce the stress and therefore increase the patient’s ability to understand, accept, and act on the information that is provided. Patients, seen in clinical practice, report that after learning new coping strategies for stress, it becomes much easier to follow dietary recommendations.

Sensitivity to Stimuli and Avoiding Monotony

Obese people are more inclined to act impulsively, avoid monotony, and respond to external cues, such as the sight or availability of food, than are people of normal weight (Rydén 2004). Instead of keeping up with dietary routines, the person easily gives in to satisfy a craving. A conflict between enjoying instant rewards and achieving long-term results develops. Stress overload sometimes decreases the threshold for responding to external cues for eating. The media and “soap operas” often portray life to be a matter of passion or pain. On the contrary, much of life consists of following routines and is often a rather monotonous story, quite unlike television drama. Establishing healthy dietary habits is especially helpful for people with low impulse tolerance.

Unsatisfactory Sleep and Fatigue

Excessive eating and obesity have been associated with disturbed or unsatisfactory sleep (Vardar 2004, Patel 2004). Many obese people suffer from sleep apnea (WHO 2009), and abdominal obesity has been strongly associated with sleep disturbances. Lack of sleep has been associated with increased levels of cortisol (Chaput 2010), and increased cortisol levels have been associated with abdominal obesity (Zinn 2010).

The literature also reports a social prejudice, even among health care personnel, against obese people as lazy and lacking willpower (Puhl 2009). In order to fight this prejudice, obese people sometimes feel the need to work harder and longer than normal-weight people. Some may unconsciously believe that excessive eating will give them strength, and they ignore sensations of fatigue or lack of energy while working harder. This trend, obviously, leads to more fatigue and can ultimately result in further weight gain.

Inability to Differentiate Between Physical and Emotional Sensations

People who grew up in an environment where neither physical nor emotional needs were met may be unable to accurately differentiate among various unpleasant physiological and emotional states (Bruch 1973, Rydén 2004). These people may overeat in response to virtually any internal arousal state. They interpret emotional distress as hunger and/or craving.

Anxiety and Other Painful Feelings

Anxiety is a general uneasiness in which someone feels a sense of danger or of an impending catastrophe. The intensity can vary. Psychological defenses protect against anxiety (Freud 1979). Some people use excessive eating as a defense against anxiety (Rydén 2004, Mills 1994, Slochower 1980, 1981). Eating and the resulting feelings of physical satisfaction can also soothe and comfort other feelings, such as anger, depressed mood, sorrow, shame, guilt, and loneliness (Adolfsson 2002, Wilson 2003, Poston 2000, Bulik 2007).

Sexual Issues

Sexual satisfaction and intimacy are important parts of life that contribute to physical and emotional well-being. Physical satisfaction that is achieved from eating can balance various forms of distress: sex anxiety, anger, sadness, sorrow, and loneliness (Cooper 1986, McDougall 1989, Rydén 2004). Oxytocin is a “calmness hormone,” released by massage, sexual arousal, and orgasm as well as by the consumption of fat (Carmichael 1987, Uuvnäs Moberg 1999). Some people achieve a feeling of balance and peace through intimate relationships that provide sexual satisfaction and support in times of distress. Others find this balance and peace through the consumption of fat.

Changes in behavior and/or in weight may impact relationships. Jeffery (2002) reports an association between weight change and the relationships between spouses. Sometimes the connection between obesity and sexuality is used to stabilize an unhealthy relationship, so that partners perceive weight changes as a threat to the relationship as they know it. If a formerly obese partner becomes more sexually active after weight reduction, it disturbs the status quo and may cause relationship problems (Marshall 1977). If sexual intimacy has previously provoked anxiety or trauma, some people learn to depend on their obesity to avoid sexually intimate situations (Wiederman 1999). King (1996) reports that obese victims of sexual abuse experience more difficulties losing weight than those who were not sexually abused, unless they receive treatment for their trauma. Because the long-term effects of sexual abuse can interfere with obesity treatment, a history of sexual abuse may be an important pretreatment variable to consider (Feldman 2007).

Interruption of Group Expectations

Eating has a social function (Jastran 2009). Meals often bring people together. Food preferences and eating and meal habits may express belonging in a social network. Social gatherings and social traditions are often centered on shared meals, where eating can function as a “social glue” and hide interpersonal discomfort. If a person’s food choices differ from the group’s usual menu, then that “glue” may deteriorate. Figure 4 illustrates how a change in one member of a group will often require change for the other members of the group.

Figure 4—Symbolic Illustration of How Change in One Area Causes Change in Another

If one person (white piece) changes, those close to him or her are also forced to change. This compounds the difficulty of lifestyle change because not only must an individual work at making the behavior change a lifestyle habit, but he or she must also deal with the responses of others to that change.

A family is a type of system in which the members know what to expect from each other. If one family member makes a lifestyle change, the family system changes, which affects the other members in that system. When one member threatens the status quo, the group’s initial reaction is to make another change, hoping to reestablish homeostasis. This reactive manipulation may include flattery, aggression, nagging, threats, or even rejection from the group. One client reported a friend telling her directly that their friendship was over if the client lost weight. Though logic questions the quality of these relationships, rejection is not a price that everybody is willing or ready to pay. Thus, it is important to address reactions and problems that might arise if the homeostasis in a social system is disturbed. Otherwise, family members’, friends’, or colleagues’ responses may block behavior change efforts (Papero 1990). A systems approach that addresses the deleterious impact of psychosocial stressors on health and lifestyle issues would help participants achieve the greatest benefits from lifestyle change activities (Porter 2010).

Physical Activity

Reduced physical activity increases risks for metabolic syndrome (Eckel 2005, Pritchett 2005). As the world has entered the 21st century, our desire for convenience, comfort, and speed has continued to influence decisions that affect our everyday lives, including how we prepare food (i.e., someone else does it) and design buildings (elevators are more convenient than stairs). But this ideological shift has even changed the way we view other less obvious lifestyle habits, such as how we clean (convenient devices never require scrubbing or any sweat), how we interact with our environment (power tools and fancy motorized kitchen utensils remove the need for working hard), and how we relax (remote controls clutter coffee tables like magazines did in years past). Driving through a fast food restaurant after working late and eating in front of the television has become normal behavior.

The 2008 Physical Activity Guidelines for Americans (CDC 2011b) recommend 150 minutes of moderate-intensity (brisk walk) aerobic activity, 75 minutes of vigorous-intensity aerobic activity, or an equivalent mix of the two each week. The guidelines also recommend muscle-strengthening activities on two or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders, and arms). Recommendations suggest that everyone, including older adults, benefit from both aerobic and muscle-strengthening activity geared to their fitness level.

The American College of Sports Medicine (Donnelly 2009) reports that some individuals require even more exercise (150–250 minutes per week of moderate-intensity physical activity) just to prevent weight gain. If our normal routine of work and/or play does not regularly include this amount of activity, we must either intentionally commit to an exercise routine or live with the bulges that store this unspent energy. Of adults over 19 years of age, an average of 46% met the 2008 recommendations for aerobic exercise and 21% met both aerobic and muscle-strengthening recommendations in 2010. Participation in physical activity was lower than this among women, older adults, and minorities (CDC/NCHS 2011).