One of the biggest questions for psychologists revolves around the idea of innate or learned traits. Are our behaviors and personality traits influenced by our genetics (nature), or do we learn them as we grow (nurture)? How we answer this question will greatly impact the types of treatments we provide for psychological disorders. The answer is still up for debate, but here are some of the things we understand now.
Most psychologists tend to look at the etiology of a psychological disorder through the biopsychosocial model. Basically, the model states that our thoughts and behaviors are impacted by our genetics (biology), our thoughts and attributions (psychology), and our environment (social). Our health is dependent on the interaction between each of these factors (Washington University School of Medicine in St. Louis).
Let’s take a look at eating disorders to investigate how the biopsychosocial model can be applied to understanding their cause. There are several different categories of eating disorders, such as anorexia nervosa, bulimia nervosa, binge-eating disorder, and other specified feeding or eating disorders. Eating disorders are characterized by a number of behaviors that cross-over between several of the disorders, such as: binge eating, purging (vomiting, laxative use, etc.), excessive exercise, fasting/restriction, and body surveillance/checking (NIH).
There is a correlation between genetics and eating disorders, in that having a close relative with an eating disorder is associated with the greater likelihood of also developing an eating disorder. Additionally, adolescence is a prominent time to develop eating disorders, and females are more likely to have eating disorders. These biological risk factors may predispose someone who encounters other risk factors to having an eating disorder.
Additionally, psychological factors may impact the development of an eating disorder. Those with higher levels of neuroticism (negative emotionality) are at a greater risk for eating disorders. Those with greater depression, anxiety, and loneliness are also at risk. According to the affect regulation model for binge eating disorders, a build-up of negative emotions will lead to an episode of binge eating in order to reduce those negative feelings (ScienceDirect). Binge eating makes a person feel better. This model supports the idea of “comfort food”, or eating to improve our emotional state. Adverse events (e.g., bullying) in childhood play a role in the development of eating disorders. If a child is repeatedly bullied, they may develop thoughts such as “I wouldn’t be bullied if I was thin,” and these cognitions lead to eating disorders.
The environment also plays a great role in the development of eating disorders. Our modern food environment (with large portion sizes, prominent unhealthy foods, and the promotion of food and body content all over social media) influences our perceptions of food and our appearance. The sociocultural model delves into how our family, peers, and the media can influence our perceptions of ourselves (NIH1). Those around us influence our conception of our appearance (through what they say and do), which leads to the internalization of the “thin ideal.” Basically, society tells us that being thin is important, and that “thin” is associated with beauty. If we do not fit this ideal, this can lead to body dissatisfaction. Our dissatisfaction can lead to disordered eating, such as restricting or binge eating episodes. Our environment impacts how we see ourselves, which in turn impacts our risk level for eating disorders.
Hopefully it’s clear that the development of eating disorders is impacted by both nature and nurture. Effective treatments may target multiple aspects (according to the biopsychosocial model) in order to improve a patient’s quality of life. Medications to suppress appetite (such as Vyvanse or Ozempic) function by affecting our biology, reducing the craving of food through changes in our brain. Interventions such as cognitive behavioral therapy (CBT) focus more on our psychology and environment. CBT works to change the overvaluation of weight and shape, helps with meal planning, and reduces dieting. Family interventions are also used to change the environment by helping families promote body positivity and encouraging the children to eat/stop restricting food.
Different interventions target different aspects of the biopsychosocial model. It’s important to understand the different types of causes of psychological disorders in order to treat these causes, and therefore treat the disorder. There is no clear answer as to whether nature or nurture is more important. What is clear is that both can play a role in our health, so it’s important to look at both to improve our quality of life.