2.3 Risk and Protective Factors of Disease

When studying diseases, whether infectious or chronic, researchers work to determine risk factors and protective factors for any given disease. A risk factor is any attribute, characteristic, or exposure of an individual which increases the likelihood of developing a disease or injury (World Health Organization, 2018). A protective factor is any attribute, characteristic, or exposure of an individual which decreases or mitigates the likelihood of developing a disease or injury (World Health Organization, 2018). Protective factors might include having safe places to exercise, positive role models, a sense of belonging in the community, or a sense of individual purpose.

Researchers agree that factors that affect health fall into one of five major categories (McGovern, Miller, & Hughes-Cromwick, 2014):

• genetics and biology (e.g., age or sex),
• health services (e.g., health insurance or access to providers),
• social circumstances (e.g., income or education),
• physical environmental factors (e.g., neighborhood or school), and
• individual behaviors (e.g., smoking or physical activity).

Click on each (i) to learn about the categories of protective and risk factors.

Factors within each of these categories influence our ability to maintain health and wellness. Some of these factors cannot be changed, like age or genetics, though some recent research shows that there are ways that environmental factors such as food, drugs, or exposure to toxins can cause changes in DNA molecules (Choquet & Meyre, 2011; Effers et al., 2017). Individuals can change others factors, at least to some extent, such as behaviors, social circumstances, and physical environmental factors.

Behavior Change is Influenced by Risk Factors and Protective Factors

Many chronic diseases are associated with behavioral risk factors—that is, the choices and behaviors made by individuals. Diet, physical activity, and substance use—alcohol and tobacco in particular—are among the most influential risk factors having an effect on the development of chronic diseases today. Even though behaviors are largely considered modifiable, individual changes are only partly a result of personal, conscious choice, as behavior is influenced heavily by larger social constructs, such as economic, educational, and environmental circumstances.

What might this look like for an individual?

• Hoa is interested in trying a diet that includes more vegetables and finds her university supports a weekly farmer’s market on campus and free nutrition and food preparation classes for students through the health promotion office. Her desired behavior change is impacted by her environment and social circumstance.
• Gwen’s mother, grandmother, and aunt have all been diagnosed with breast cancer, demonstrating a predisposition in their family to cancer. Gwen would like to start screenings for this before the recommended age, but her employer’s health plan won’t cover early screening and she has difficulty paying for it out of pocket without picking up extra shifts. Gwen’s health concerns stem from a combination of genetics, health services, and social circumstances.
• Nels is interested in starting a new walking routine after work in the evenings but is limited to where they can walk; they have determined that it isn’t safe or appropriate to walk in the evenings where they live and cannot currently pay for a membership at a nearby health club or gym or buy a treadmill for their home. Nels’ behavior change is influenced by their environment and social circumstances.
• Wyatt is interested in quitting tobacco. Fortunately, his health insurance plan and state health department both provide support services for tobacco cessation, and he has started taking a brief walk during his employer-assigned work breaks rather than using it to have a cigarette. His desire to make a behavior change is supported by both his health services and environment.

Risk Factors Do Not Always Lead to Disease

Risk factors within each of the five categories are often observed and measured at a population level to help predict likelihood of individuals developing chronic disease. This means that having one or more risk factors does not guarantee that someone will develop that disease, but it does increase their likelihood. Protective factors within each category can help mitigate some adverse conditions that increase risk. Many elements come into play to determine health and health risk.

Obesity as a Risk Factor

We’d like to discuss one specific risk factor more in-depth: obesity. Research and debate persists in the medical community about whether obesity should be considered a disease or a risk factor. Obesity and where fat is stored in an individual’s body are linked, along with other risk factors, to outcomes like heart disease and diabetes and can have many causes, including an individual’s biology, like genes, hormones, or brain functioning. Abdominal fat that surrounds the organs is called visceral fat and some research has connected this location of fat to outcomes like cardiovascular disease, cancer, and type 2 diabetes (Ritchie & Connell, 2007; Després et al., 2008; Effers et al., 2017). Other causes of chronic diseases are behavioral, like inactivity and poor nutrition (Choquet & Meyre, 2011; Effers et al., 2017). By defining obesity as a disease, the medical community is better able to fund research and treatment for those people who are experiencing negative health outcomes associated with weight; this is a major contributing factor to the birth of the entire field of obesity prevention.

Regardless, there is no one best measure for determining health and we should not rely on things like weight, body composition, or appearance to determine overall health.