Although a person rarely plans to become addicted, repeated use, particularly of certain substances, will eventually lead to addiction. It is difficult to say when the repeated use of a substance or activity will shift from being harmless to harmful. These effects may not be noticeable at first, but as the problem grows, addictive behaviors can be extremely harmful to a person's health and well-being, as well as to relationships with family and friends. A problem is apparent as soon as use of a substance begins to harm a person in any part of their life. Addictive behaviors often involve substance abuse, which is the repeated use of one or more chemical substances that alter mental state and cause behavioral change.
Nicotine addiction has powerful negative effects on the smoker's health.
Caffeine dependence does not appear as harmful, but can produce unpleasant symptoms and can lead to changes in heart rate, blood pressure and other health hazards in some people. Addictive behavior may also involve other non-chemical substances or practices, such as food, gambling, sex, and even work or exercise. While the use of mind-altering chemicals can result in physical dependence, the psychological craving related to these substances and other addictive behaviors can be just as strong. Both physical and psychological dependence often need treatment to break the addiction cycle. These feelings are evidence of withdrawal needing to take more and more of a substance or practice a behavior for longer and longer periods of time to achieve the desired effect.