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Several Surprising Side Effects of Smoking Weed

There are several significant side effects of weed smoking. According to the National Institute on Drug Abuse (NIDA), it is the most commonly used illicit drug globally. However, the marijuana landscape in the United States is shifting. 

  • 70% of High School Seniors responded to the question of the side effects of smoking marijuana by answering, “No Side Effects.”


From a public health standpoint, such widespread use of the drug has raised quite a few concerns, including:

  • Heavy use can stunt brain development in users until around the age of 25 when the brain reaches maturity.
  • Reduces thinking, learning, and memory functions that can be permanent
  • Ongoing chronic use, one study suggests, results on average in an eight-point IQ loss between the ages of 13 and 38
  • Possibly cause breathing problems, which lead to an increased risk of chronic lung infections or lung-related illnesses.
  • Raises the heart rate, which can increase the likelihood of heart attack, especially among older users or those with existing heart problems
  • Pregnant women who smoke weed risk causing both brain and behavioral issues in their child
  • Worsens mental health conditions, such as depression, anxiety, bipolar disorder, schizophrenia, and suicidal thoughts
  • On average, research suggests one out of every 11 marijuana users becomes addicted to the drug.

 Researchers have gathered only a limited amount of information. The Drug Enforcement Administration (DEA) still lists marijuana as a Schedule I drug.

The University of Texas at Dallas conducted a study using MRI on subjects that do not use pot and those that use it three times a day. Assistant professor at UTD and founder of Advance MRI, Dr. Sina Aslan, said of the study’s results;

  • “…the structural connectivity or ‘wiring’ in the brain starts degrading with prolonged marijuana use.”

A fascinating 2015 Pew Research survey found that nearly 70 percent of U.S. citizens believe drinking alcohol regularly is more harmful to their health than smoking marijuana. Do we know enough about the long-term side effects of smoking weed to assume it is “better” for you than drinking alcohol? And why do so many people think smoking marijuana isn’t detrimental to your health?

Memory, emotion and learning

Specific characteristics are in chronic marijuana users:

  • Poor working memory (for example, forgetting how to install a car battery soon after being shown by a mechanic how to do it)
  • Impaired executive functioning (ability to manage time, plan, organize, and remember details)
  • A decline in cognitive processes (lower IQs than non-users)

Although over 400 chemical compounds are in marijuana, most of the side effects experienced are THC, the primary psychoactive substance in cannabis. Prevalent in the brain, cannabinoid receptors readily accept THC and facilitate its ability to induce neural changes in the brain that lead to alternations in various cognitive processes.

Neuroimaging studies investigating the effects of chronic pot use have found potentially permanent alterations in the brain structure of frequent marijuana smokers. Scientists are very interested in the hippocampal area of the brain. The hippocampus controls memory, emotion, and learning. Studies indicate that long-term adult cannabis users present reduced right hippocampus volume.

Another study involving young adults (18 to 20 years old) heavy marijuana users revealed the same adverse effects on hippocampal volume. Thus, researchers conclude that decreased hippocampal volume may also reinforce risk factors for young adults to develop severe cannabis dependence.

Heroin, cocaine, methamphetamine, prescription pain pills, barbiturates, and marijuana all exhibit similar pharmacokinetic properties as marijuana, including:

  • Rapidly absorbed by the body
  • Quick entrance into the central nervous system (spinal cord and brain)
  • High bioavailability (in other words, little of the drug once it enters the body)
  • Short half-lives (the effects of addictive drugs do not last long because they are quickly metabolized and eliminated by the body)
  • Addictive substances primarily target the brain)

Liver disease

A 2005 literature review found that endocannabinoids may be “involved in several aspects of acute and chronic liver disease, including vascular changes, modulation of the inflammatory process and neurological function.”

Testicular cancer

A 2012 study involving healthy men and men diagnosed with testicular cancer suggested a correlation between pot use and the risk of developing it.

Lung disease

Pooled analysis results published in the International Journal of Cancer did not find solid evidence that chronic pot-smoking increased a user’s risk for lung cancer. However, the report’s authors reiterated that “the possibility of potential adverse effects for heavy [marijuana] consumption is real.”

According to the American College of Cardiologists report, “Using marijuana raises the risk of stroke and heart failure even after accounting for demographic factors, other health conditions and lifestyle risk factors such as smoking and alcohol use, according to research scheduled for presentation at the American College of Cardiology’s 66th Annual Scientific Session.”

Respiratory disorders

Longitudinal studies of habitual pot smokers indicate they experience multiple respiratory symptoms (wheezing, coughing, sputum) similar to those experienced by cigarette smokers. Moreover, bronchial biopsies of chronic cannabis and tobacco smokers show “significant bronchial mucosa histopathology,” or disorders of the bronchial tissues.

zip of weed…