Here are just a few of the health effects you may want to know:

• Marijuana use directly affects the brain [12]—specifically the parts of the brain responsible for memory, learning, and attention.
• The compounds in marijuana can affect the circulatory system [12] and may increase the risk of heart attacks [13] and strokes [14].
• Smoking marijuana [12] can lead to a greater risk of bronchitis, cough, and phlegm production.
• Marijuana users are significantly more likely than nonusers to develop chronic mental disorders [12], including schizophrenia. Schizophrenia is a type of mental illness where people might see or hear things that aren't really there (hallucinations).
• Eating foods or drinking beverages that contain marijuana have some different risks than smoking marijuana, including a greater risk of poisoning [12].
• About 1 in 10 marijuana users will become addicted [12]. For people who begin using before the age of 18, that number rises to 1 in 6.
• Some research shows that using marijuana while you are pregnant[288 KB] [15] can cause health problems in newborns—including low birth weight and developmental problems.
• Marijuana use can slow your reaction time and ability to make decisions when driving[271 KB] [16].