L21 & L22 | Obesity IV

Obesity IV

• This lecture concludes the examination of treatment options for obesity, including exercise, behavioral therapy, drugs, and surgery.
• The lecture then turns to a related topic: body image and weight control among healthy-weight individuals.

Exercise I

• Regular exercise offers several benefits for treating obesity: increased weight loss, improved glucose tolerance, blood pressure regulation, improved lipid profiles, increased muscle mass, better long-term dietary compliance, and improved mood.
• The CDC and the US Surgeon General recommend 30 minutes of moderately intense physical activity per day (e.g., brisk walking).
• The Institute of Medicine and the International Association for the Study of Obesity suggest twice that amount.
• As people become more physically fit, they tend to lose abdominal fat that is replaced by muscle.

Exercise II

• Moderate-intensity exercise raises the heart rate to 55-69% of maximal heart rate, allowing for conversation but not singing.
• Maximal heart rate is calculated as 220 minus the person's age.

Exercise III

• 70-75% of adults fail to meet even the recommended guidelines for exercise.
• Both healthy and obese individuals face difficulties initiating and maintaining exercise programs.
• Behavioral therapy and lifestyle programs can address this issue by integrating physical activity into daily life.

Behavior Therapy I

• Almost all obesity interventions incorporate behavioral therapy.
• The goal is to identify behaviors that encourage overeating and to help establish healthy eating and exercise behaviors.
• Key methods include identifying appropriate goals and identifying ways to achieve those goals, including using small incremental changes (shaping).

Behavior Therapy II

• Self-monitoring (detailed food and exercise diaries): reveals hidden eating patterns and discrepancies in self-reported vs actual food intake.
• Stimulus control: involves identifying cues to eating and implementing strategies to control those cues (e.g., removing uneaten food, serving smaller portions).
• Cognitive restructuring: redirects negative self-talk and fosters a more adaptive approach to dealing with setbacks (e.g., viewing a lapse in diet as a temporary misstep instead of a total failure).
• Time-limited therapy sessions (individual or group format) combined with exercise produce better outcomes.

Behavior Therapy III

• Behavior therapy with dieting is significantly more effective than dieting alone in the short-term (weight loss of 5-10% vs. roughly 5%).
• Compliance with therapy is better (80%) when behavior therapy is used.
• Whether behavior therapy alone leads to better long-term weight loss is not yet definitively known.
• Phone and internet contact with therapists can facilitate weight maintenance longer-term, though this is not definitively agreed on.

Medication I

• The history of drug treatments for obesity is often mixed, with past drugs having concerning side effects.
• Amphetamines and fenfluramine/dexfenfluramine were previously used but were subsequently withdrawn due to adverse effects (pulmonary hypertension, anxiety, depression, suicide).
• Some newer medications (e.g., sibutramine, rimonabant) have been withdrawn due to safety concerns.

Medication II

• Current approaches to obesity medications involve centrally acting drugs (e.g., phentermine, topiramate) and peripherally acting drugs (e.g., orlistat, cetilistat).
• These medications can reduce weight, especially in the short-term, but need to meet effectiveness thresholds (e.g., 5% weight loss compared to placebo) to be considered viable for general use.

Surgical Treatment

• Restrictive procedures (e.g., gastric banding, vertical sleeve gastrectomy).
• Malabsorptive procedures (e.g., Roux-en-Y gastric bypass, endobarrier).
• Two types of surgical procedure are generally available, either in combination or alone.

Roux-en-Y Gastric Bypass

• Patients typically lose a significant amount of weight (50-60% of their initial body weight) after surgery.
• Continual medical supervision is required post-op.

Weight Loss

• Many individuals desire to lose weight but face consistent struggles.
• Surveys consistently indicate that a majority of participants desire to lose weight and attempt to do so, but are unsuccessful.
• Weight loss is often associated with other factors such as body image dissatisfaction, family influences, and exposure to media images.

Body Dissatisfaction

• Body image dissatisfaction, measured in several ways, is a significant factor that motivates weight loss attempts.
• Methods include measures such as self-reported perceptions and discrepancies between perceived and ideal body image.
• This dissatisfaction is highly prevalent in normal-weight populations, particularly women, though men are affected as well.
• It appears to worsen in westernized nations and increase with cultural acculturation.

So Why Are People Dissatisfied?

• The media plays a role in perpetuating unrealistic and unhealthy body image standards.
• The media portrayal of thin women and muscular men is highly non-representative of the overall population, leading to greater body dissatisfaction, especially in women.
• Family and upbringing influences also significantly impact body image perceptions and motivate weight-loss attempts.
• Body image dissatisfaction is not unique to obese people but can affect people of different weights, ages, and background.

Chronic Malnourishment

• Malnourishment can be chronic and/or acute.
• Chronic malnutrition, particularly in children, can lead to several long-term health and cognitive issues, such as stunting and a lower IQ.
• Famine frequently leads to temporary or long-term malnutrition, with many societies seeing this as a recurrent issue.
• The social aspects of famine and malnutrition are prevalent in many places around the world and can have many consequences on people's lives.

Psychological Effects of Famine

• Famine can result in a wide range of physiological and psychological consequences.
• Physiological effects in both children (e.g., PEM as a continuum between marasmus and kwashiorkor) and in adults.
• The socio-physiological effects of starvation are significant.
• The psychological effects of starvation can potentially persist long after the famine has ended.
• Psychological effects from being part of a famine study, in some cases, were more extreme than when just examining the psychological effects of starvation.

Food Deprivation and Longevity

• Though not supported fully, several studies have shown a link between food deprivation and increased lifespan in animals.
• The relationship is not as straightforward with humans and still requires more understanding.

Conclusion

• Acceptance of a healthy body image is crucial, along with the recognition that malnourishment can have significant negative consequences, and the need for preventative measures.
• There needs to be a better understanding of the relationships between body image and society, diet, and body image, along with mental health.