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The Effects of Smoking Marijuana

Many people assume that marijuana isn’t really a threat to health. But the drug has changed in recent years. The potency of a major ingredient – THC – has recently increased 10 t0 20 times. And researchers are discovering new, disturbing facts about the effects of marijuana on the body. For example:

• A UCLA study of habitual marijuana smokers found that pot can be even more damaging to the lungs than cigarettes. Smoking about three joints a day affects the lungs as much as smoking 20 cigarettes.
• Researchers at the University of Illinois at Chicago have found that THC, the active ingredient in marijuana, may disrupt the complex chemistry of the immune system, diminishing the body’s ability to fight off disease-causing viruses and bacteria.
• A study at Wake Forest University’s Bowman Gray School of Medicine reports that laboratory animals exposed to THC five times a week for a period of eight months showed a significant decrease in nerve cells in the vital part of the brain that plays a role in emotional behavior. The decrease in nerve cells seems to mimic the aging process.
• Heavy use of marijuana can disrupt hormone production in both males and females, cutting down the level of testosterone and sperm cells in men and interfering with menstrual cycles and ovulation in women.
• You don’t have to actively use marijuana to experience some of its effects and damage. Hanging out with marijuana smoking friends and inhaling secondhand smoke from their joints can affect you more than you realize. According to a recent study at the National Institute of Drug Abuse Addiction Research Center, being exposed to the equivalent of only four joints in an hour can make you come out positive on a drug test!

Dr. Wibbelsman, M.D., is an award-winning author and former “Dear Doctor” columnist for Teen magazine. Chair of Adolescent Medicine for the Permanente Medical Group, Northern California, he is chief of the Teen-Age Clinic at Kaiser Permanente Medical Center in San Francisco, and an associate professor of pediatrics at the University of California, San Francisco Medical School. Dr. Wibbelsman is the news anchor for a Bay Area television series, “Medicine in the Nineties”.


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