Unlike the cigarette habit, occasional pot smoking does not seem to trigger declines in lung function that could lead to breathing problems, a recent 20-year study suggests.
"Tobacco takes you down that road toward breathlessness, but low to moderate levels of marijuana don't," said study coauthor Stefan Kertesz, MD, associate professor, University of Alabama at Birmingham.
Okay To Party In Moderation?
But there were limits to the study. For example, the findings do not indicate whether occasional (two or three joints a month) pot smokers face a higher risk of lung diseases such as cancer.
And it is clear that marijuana smoke irritates the lungs, causing coughing and sputum production, and addiction to marijuana obviously causes problems, noted Dr. Kertesz. However, as with alcohol and other drugs, the question of harm becomes more ambiguous when it comes to more occasional users who aren't addicted, he said.
"What about the adults who use three joints of marijuana a month for many years?" he said. "Clarifying that is actually quite difficult."
Nevertheless, the research should fuel the ongoing debate over medical marijuana, which critics say is too hazardous to serve as a drug to treat conditions such as pain.
In the recent study, researchers examined the findings of another study, which began in 1985, of more than 5,100 people ages 18 to 30 from California, Chicago, Minneapolis and Alabama. Researchers regularly asked participants about past and current use of cigarettes and marijuana.
Every few years over two decades, the participants took lung tests that measured their lung function through their ability to blow hard into a tube.
The typical tobacco user smoked eight to nine cigarettes a day, while the marijuana users in the study smoked about two to three times over the past 30 days. "That's really different from ('pothead' film icons) Cheech and Chong," he said. "Americans who smoke marijuana typically don't smoke it every day.
Respiratory risks did seem to rise with the intensity of marijuana use, however. The study authors found increasing evidence of lung trouble among people who smoked marijuana more heavily (20 or more times a month).
The study findings appeared in the Journal of the American Medical Association.
Dr. Kertesz said that research has consistently shown that "with tobacco smokers, the more use of tobacco that's accumulated, the more airflow and lung volume is lost over time." But that wasn't the case with mild to moderate users of marijuana, he and his colleagues found.
Experts Weigh In
Robert Hancox, MD, associate professor, department of preventive and social medicine, University of Otago, New Zealand, praised the research. But he also believes that pot smoking has negative respiratory effects.
"Smoking marijuana definitely harms the lungs," said Dr. Hancox. "Several studies have clearly shown that even light marijuana smokers can develop severe bronchitis with symptoms of cough and phlegm production. Studies have also demonstrated that smoking marijuana leads to abnormal lung function, but using different tests than those used by this study, What this study shows is that the pattern of lung damage seen with marijuana is not the same as caused by tobacco."
And one advocate against drug abuse noted that the study has a variety of limitations.
"A significant problem is that cannabis use is often difficult to quantify precisely due to smokers sharing joints, different inhalation techniques and different ways of smoking cannabis, including joints, pipes and bongs," said Calvina Fay, executive director of Drug Free America Foundation. "By comparison, the average amount of tobacco in a commercial cigarette of standard length is 1 gram."
Also, Fay said, "it is important to not forget the numerous other serious consequences of marijuana use," such as cognitive and learning problems, psychosis, addiction, criminal behavior and impaired driving, "none of which were considered in this study."
On the other side of the argument is Paul Armentano, deputy director of the national promarijuana group NORML. He said that people can now virtually eliminate the lung-irritating effects of marijuana by using vaporizer devices.
Armentano added that, in his opinion, science has determined alcohol, tobacco and prescription drugs "to be far more dangerous and costlier to society than cannabis," but they are regulated instead of banned.
Use Zinc to Stop a Cold
Some studies show that people who take zinc within a day of the first evidence of illness develop milder symptoms and/or feel better more quickly. Try a lozenge or syrup to get the zinc into direct contact with the cold virus in your throat. The upper limit for zinc is 40 milligrams a day for adults, but many studies have used slightly higher amounts, which probably are safe if taken for only a few days.
Side effects: Nausea and bad taste in the mouth.
Three Great Herbal Cold Remedies
If you're concerned about the sleepy side effects from over-the-counter cold medicine, try the following herbal formulas…
- Rosemary clears congestion. Place one-half cup of crushed leaves in the toe of hosiery, and soak it in a tub of warm water for 20 minutes. Breathe in the aroma.
- Sage relieves a sore throat. Make a tea by steeping two teaspoons of crushed leaves in eight ounces of hot water for 20 minutes. Strain, and add one teaspoon of sea salt. Gargle with the liquid for 30 seconds, then spit it out. Repeat as necessary.
- Thyme unplugs sinuses. Pour three cups of boiling water over two tablespoons of crushed thyme leaves in a bowl. Cover your head with a towel, and lean over the bowl. (Don't let the steam burn you.) Close your eyes, and breathe in deeply for eight to 10 minutes.