Professor Richard Beasley from the Medical Research Institute of New Zealand has studied the effects of marijuana on the lungs.

For chronic users, smoking just 1 joint is as bad for the lungs as 2.5 to 5 cigarettes.

First, the details.

• Adults were recruited into 4 smoking groups.
• Cannabis only
• Tobacco only
• Combined cannabis and tobacco
• Non-smokers of either substance
• Their respiratory status was assessed using high-resolution CT scanning, pulmonary function tests, and a respiratory and smoking questionnaire.

And, the results taken from the Medscape review

• Cannabis smoking was associated with an increased risk of wheeze, chest tightness, and cough.
• Cannabis smokers had twice the risk of chronic bronchitis.
• They had a 70% increased risk of asthma diagnosed after age 16 years.

The bottom line?
“Long-term cannabis smoking increases the risk of lung damage, causing both asthma and chronic bronchitis,” Dr. Beasley said.

Smoking 1 cannabis joint causes as much damage to the lung as 2.5 to 5 tobacco cigarettes.

12/15/07 09:18 JR