Why Do We Engage in Unhealthy Behavior?
Most adults know what healthy and unhealthy practices are. We know that smoking, over-drinking, eating high-fat foods, etc. are bad for us. We also know that exercise, medical testing, wearing out seatbelts, etc. are good for us.
But, why do some of us discontinue our unhealthy habits and take on healthy habits, and some of us don't? It's obviously not an issue of knowing what is healthy. Other psychological factors are involved.
This article will discuss the three most accepted theories on why we do or don't change our health behaviors:
- The Health Belief Model (HBM)
- The Theory of Planned Behavior (TPB)
- The Transtheoretical Model (TTM)
The Health Belief Model
Victor Strecher and Irwin Rosenstock used this model to explain how we decide to behave in certain ways. The model focuses on our beliefs or perceptions and contains four interacting factors:
- Perceived susceptibility: The greater our perceived susceptibility, the stronger the motivation to engage in healthy behaviors. (Do I really believe I will die from smoking?)
- Perceived severity of the health threat: The greater the perceived seriousness of the condition (pain, death) and how these conditions would affect our friends and family, the harder we tend to work toward changing our unhealthy behaviors.
- Perceived benefits and barriers of treatment: We normally weigh the benefits against the barriers in deciding to give up an unhealthy practice. (Do the benefits outweigh the costs?)
- Cues to action: Advice from friends, media health campaigns, and other factors like age, socioeconomic status, and gender play a part in our beliefs about pursuing a more healthy lifestyle.
The Theory of Planned Behavior
Though the HBM and TPB are similar, the TPB focuses not so much on variable beliefs, but more on how attitude variables affect behavior. Icek Ajzen's theory states that the best way to predict a change in behavior is to examine the person's behavioral intention - the decision to engage in a behavior or not.
- Attitude toward the behavior: Do we really believe that eating a low-fat diet will lead to better health and appearance?
- Subjective norm: Are we motivated to comply with the views of others and experts about the behavior in question? Alternately, if all of our friends and family eat high-fat diets, will we maintain an accurate view of the harm this type of diet causes?
- Perceived behavioral control: Do we believe that we will succeed in the new behavior?
TPB also touches on behavioral willingness versus behavioral intention. This concept applies mostly to negative health behaviors. For instance, we may plan not to drink at a party we're heading to, but if all of our friends there are drinking, are we willing to join in?
The Transtheoretical Model
James Prochaska introduced the TTM to explain how behavior changes progressively through stages: (Picture a spiral starting with 1 at the bottom.)
- Precontemplation (Not Ready): I don't intend to take action in the foreseeable future, and I'm not even sure the behavior is a problem.
- Contemplation (Getting Ready): I'm starting to recognize that my behavior is a problem, and I'll start considering the pros and cons of making the change.
- Preparation (Ready): I intend to take action now, and I start taking small steps toward my behavior change.
- Action: I've modified my unhealthy behavior and am acquiring new healthy behaviors.
- Maintenance: I've been able to sustain the new behavior for a while and am working to prevent a relapse.
- Termination: I am sure that my new behavior is permanent and am not at all tempted to return to my unhealthy habits.
This stages of change model accounts for those of us who move up and down the stages or might get stuck in one stage. It's also beneficial because a health care professional can identify the stage we are in and design an intervention or treatment to help us reach the next stage. For example, if a smoker is in the precontemplation stage (doesn't really believe he will die from the habit), he probably won't stop smoking unless someone intervenes to educate him or even just encourages him to start thinking about giving up the habit.
Why We Don't Make Good Health Decisions
Taken in combination, these three models of health behavior change, work well to help us understand why, despite having knowledge of the impact, we may not be making the best health decisions.