Weed, or marijuana, is generally consumed by smoking the leaves of the plant, usually in a pipe or a joint rolled from cigarette paper. The National Institute of Drug Abuse, or NIDA, reports that in the United States marijuana is the most commonly used illegal drug. Smoking marijuana seems to have fewer risks than other drugs, but the consequences are still very high and generally not worth it unless it is part of a prescribed treatment plan.
Chemical Changes
When a person smokes weed, the chemicals known as delta-9-tetrahydrocannabinol, or THC, pass through the body and into the brain. According to the NIDA, THC affects the cannabinoid receptors in a person's brain; this can lead to problems with coordination; difficulty concentrating, focusing or problem solving; and trouble with learning and memory.
Addiction
Weed is a drug, and as with any drug a person can become addicted to it. The NIDA reports that when long-term users attempt to stop smoking marijuana, they begin experiencing symptoms of withdrawal within one day. A person who becomes addicted to weed will continue to consume despite, the negative impact it has on her life.
Gateway Drug
Smoking weed can lead to the use of other more severe drugs. Experiencing the high feeling associated with smoking marijuana can lead to a desire to try other drugs such as acid, cocaine, heroine and LSD. The generally low-risk nature of marijuana can lead consumers to be less inhibited about trying other drugs. Many of the drugs that people try, after they have used marijuana, are highly addictive and can have significantly higher-risk side effects.
Having Children
Smoking marijuana regularly can have affects on a person's fertility. TeensHealth reports that regular marijuana use can negatively affect the amount of sperm a man can produce and the regular ovulation cycle of a woman. In addition, if a fetus is exposed to marijuana smoke, behavioral and developmental problems may result as the child grows, notes TeensHealth.
Breathing
Smoking marijuana can lead to an increase in mucus production, chronic cough and bronchitis, notes TeensHealth. Similar to smoking cigarettes, smoking marijuana damages your airway passages. People who smoke marijuana can develop labored breathing, which can make physical activity harder to endure.
Blood Flow
The continued use of marijuana can cause a person's blood pressure to decrease, notes TeensHealth. This reduction in blood pressure may result in a person having dizzy spells and being unable to fight off infections and other diseases, notes TeensHealth.
Mental Health
Marijuana use can affect a person's overall mental health. Smoking weed may increase the risk of developing depression, anxiety disorders and schizophrenia, notes TeensHealth. A person may smoke marijuana in an effort to reduce the symptoms associated with a mental health disorder, but the intake of marijuana can actually cause a person to become more symptomatic.


