Addiction Drug Use Marijuana The Negative Health Effects of Marijuana By Buddy T facebook twitter Buddy T is an anonymous writer and founding member of the Online Al-Anon Outreach Committee with decades of experience writing about alcoholism. Learn about our editorial process Buddy T Medically reviewed by Medically reviewed by Steven Gans, MD on December 02, 2020 Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital. Learn about our Review Board Steven Gans, MD Updated on December 02, 2020 Print Marc Romanelli / Getty Images Table of Contents View All Table of Contents Short-Term Effects Brain Heart Bone Health Lungs Cancer Risk Exposure During Pregnancy Although legalization activists and many marijuana users believe smoking pot has no negative effects, scientific research indicates that marijuana use can cause many different health problems. Marijuana is one of the most commonly used drugs in the United States. When smoked, it begins to affect users almost immediately and can last for 1–3 hours. When it is eaten in food, such as baked in brownies and cookies, the effects take longer to begin, but usually last longer. Short-Term Effects of Marijuana The short-term effects of marijuana include: Difficulty thinking and problem-solvingDistorted perception (sights, sounds, time, touch)Increased heart rateLoss of coordinationProblems with memory and learning Sometimes marijuana use can also produce anxiety, fear, distrust, or panic. Brain Side-Effects of Marijuana Usage The active ingredient in marijuana, delta-9 tetrahydrocannabinol or THC, acts on cannabinoid receptors on nerve cells and influences the activity of those cells. Some brain areas have many cannabinoid receptors, but other areas of the brain have few or none at all. Many cannabinoid receptors are found in the parts of the brain that influence pleasure, memory, thought, concentration, sensory and time perception, and coordinated movement. When high doses of marijuana are used, users can experience the following psychotic symptoms: DelusionsDisorientation/disorganizationHallucinations Marijuana's Negative Effects on the Heart Within a few minutes after smoking marijuana, the heart begins beating more rapidly and the blood pressure can rise. According to a review published in 2017, marijuana users' risk for a heart attack increases after smoking marijuana, compared to their general risk of a heart attack when not smoking. Marijuana's Impact on Bone Health Research published in 2017 found that people who smoke large amounts of marijuana on a regular basis have reduced bone density, which can increase the risk of bone fractures. The study at the University of Edinburgh used DEXA-scan x-rays and found that heavy users of marijuana had a lower body weight and a reduced body mass index (BMI), which could contribute to loss of bone density. Heavy users were defined as those who had smoked more than 5,000 times during their lifetime. However, another study published in 2017, looked at survey and health information for almost 5,000 adults and didn't find any association between decreased bone density and marijuana use. How Marijuana Affects Lungs Smoking marijuana, even infrequently, can cause burning and stinging of the mouth and throat, and cause heavy coughing. According to a review published in 2019, scientists have found that regular marijuana smokers can experience many of the same respiratory problems as tobacco smokers do, including: Daily cough and phlegm productionIncreased risk of lung infectionsMore frequent acute chest illnesses Most marijuana smokers consume a lot less cannabis than cigarette smokers consume tobacco, however, the harmful effects of smoking marijuana should not be ignored. Marijuana contains a similar amount of carcinogenic hydrocarbons as tobacco smoke and because marijuana smokers typically inhale deeper and hold the smoke in their lungs longer than tobacco smokers, their lungs are exposed to those carcinogenic properties longer, when smoking. Cancer Risk and Marijuana History According to a review published in 2015, one study found that marijuana smokers were three times more likely to develop cancer of the head or neck than non-smokers, but that study could not be confirmed by further analysis. Because marijuana smoke contains three times the amount of tar found in tobacco smoke and a number of carcinogens, it would seem logical to deduce that there is an increased risk of lung cancer for marijuana smokers. However, researchers have not been able to definitively prove such a link. Even though researchers have yet to "prove" a link between smoking pot and lung cancer, regular smokers may want to consider the risk, and further research is needed. Marijuana Exposure During Pregnancy Several studies have found that children born to mothers who used marijuana during pregnancy exhibit some problems with neurological development. These can include: HyperactivityImpulsivityProblems with executive functionProblems with sustained attention and memory Was this page helpful? Thanks for your feedback! Learn the best ways to manage stress and negativity in your life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. National Institute on Drug Abuse. Most Commonly Used Addictive Drugs. National Institute on Drug Abuse. Marijuana. Noble MJ, Hedberg K, Hendrickson RG. Acute cannabis toxicity. Clin Toxicol (Phila). 2019;57(8):735-742. doi:10.1080/15563650.2018.1548708 Goyal H, Awad HH, Ghali JK. Role of cannabis in cardiovascular disorders. J Thorac Dis. 2017;9(7):2079–2092. doi:10.21037/jtd.2017.06.104 Sophocleous A, Robertson R, Ferreira NB, Mckenzie J, Fraser WD, Ralston SH. Heavy Cannabis Use Is Associated With Low Bone Mineral Density and an Increased Risk of Fractures. Am J Med. 2017;130(2):214-221. doi:10.1016/j.amjmed.2016.07.034 Bourne D, Plinke W, Hooker ER, Nielson CM. 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