Risk & Protective Factors


As with many other diseases, vulnerability to substance use disorder (SUD) differs from person-to-person, and no single factor determines whether someone will become addicted to alcohol or drugs. In general, the more risk factors a person has, the greater the chance that using substances will lead to a SUD. For every risk factor, there is a protective factor to counterbalance it.


These factors can be environmental (conditions at home, at school, and in the neighborhood), biological (a person’s genes, stage of development, and even their gender or ethnicity), psychological (impulsive personality), or behavioral (age of first use, types of substances used and how they are used).

Certain risk factors are more powerful than others during various stages of development. Peer pressure, for example, tends to be strongest during the teenage years. A strong parent-child bond has a greater impact on reducing risks during the early years of life. Evidence-based prevention programs often focus on intervening early in a child’s development to reduce risk factors and strengthen protective factors before problem behaviors develop.

Early childhood risk factors, such as exposure to violence and trauma, can be addressed with family, school, and community interventions that focus on helping children learn strategies to control stress and develop appropriate, positive behaviors. If left unaddressed, negative traits and behaviors (such as impulsivity and aggression) tend to attract more risk factors (such as academic failure and social difficulties), which put children at further risk for substance use and SUDs.


What environmental factors can increase risk?
  • Home and Family - The influence of the home environment is very important, especially during childhood. Children exposed to significant stress such as housing and food instability, violence, or trauma are at increased risk. Children who live in the same household as a parent or family member who misuses alcohol or drugs, or engages in criminal behavior, are also at an increased risk of developing a substance use disorder later in life.

  • Peer and School - A person’s friends and acquaintances have a strong influence over their behavior, especially during adolescence. Substance-using peers can inspire an individual without any risk factors to try drugs for the first time. Academic struggles or poor social skills can also increase one’s risk of misusing alcohol and drugs.

  • Community - Community level factors, such as high availability of drugs and alcohol, a permissive culture around substance use, and lack of economic opportunity can all increase the risk for substance use and SUD among people in the community.

What biological factors can increase risk?

Genetics account for about half of a person’s risk for SUD. While we can’t change our genetics, knowing about a family history of addiction and understanding the role of genetics in SUDs can empower both adults and adolescents to take critical steps to boost protective factors and reduce other risk factors—by delaying initiation of substance use.

Other biological factors that can influence risk include the effects of environmental factors on the function and expression of a person’s genes, a person’s stage of development (age), and their mental and physical health. People with mental health disorders such as depression and anxiety are at a greater risk for problematic substance use than the general population.

What psychological traits can increase risk?

Some traits are linked to increased risk for substance use and SUD, including:

  • Impulsivity

  • Sensation-seeking

  • Anxiety sensitivity

  • Stress-reactivity

  • Aggressiveness

What behavioral factors can increase risk?
  • Early Use - Although using alcohol or drugs at any age can lead to a substance use disorder, research shows that the earlier a person begins to use substances, the more likely he or she is to develop serious problems. This is due to the harmful effect that substances can have on the adolescent brain, which does not finish developing until a person is in their early to mid-20s.

  • Method of Administration - In general, the faster a substance affects the brain and the stronger the effect, the more addictive it is. Smoking or snorting a drug or injecting it into a vein (as opposed to chewing or swallowing) increases its addictive potential because these methods cause the drug to enter the brain within seconds, where it activates the brain’s reward system.