The marijuana potency myth is like a zombie in a George Romero film - it. just. won’t. die!

Marijuana more potent than it used to be | IndyStar.com | The Indianapolis Star
Think marijuana is the drug of yesterday? Think again. According to a recent article in Good Housekeeping magazine, not only does the intoxicating weed remain a drug of choice, it’s a lot stronger than it used to be. In 1970, the average level of THC (the active ingredient in marijuana) was less than 1 percent. By 2006, it had risen to 7 percent. In addition, research shows that one joint can harm airways as much as five cigarettes. The reason: Marijuana cigarettes don’t have filters and the smoke is inhaled deeply.

Well, Good Housekeeping said so, so it must be true!

At least they do us the courtesy of only claiming a greater than 7x increase, instead of the “25-fold increase” Barbara Kay likes to throw around.

The lowest THC average in a meta-analysis of hundreds of studies of marijuana seizures in America and abroad, we find the lowest averages to be 2% and the highest averages to be 4% for marijuana seized from 1975-1983.  Marijuana with 1% THC is otherwise known as “industrial hemp”, and smoking that will give you more headache than high.

THC levels have risen, to averages of 5% to 8½%.  Some of the highest quality (and rarest) marijuana seized has THC levels of 33%.  (Of course, these pale in comparison to synthetic THC in Marinol, which is 100% pure, but for some reason, considered a safe medicine.)

But with THC, an increase in potency is not an increase in harm.  It is non-toxic, no matter how pure it is.  You do not get any less or more high depending on potency, you just need more or less cannabis to get high.

Which leads to the point about “one joint = five cigarettes” (at least this time it’s not “twenty”) — if the smoking is so harmful, wouldn’t you want someone to have a joint with the 8% THC rather than the 2% THC?  They’re going to only have to take a couple of puffs on the 8% joint, but they’ll probably have to finish the entire 2% joint for the same effect.  Don’t you want less smoking?

But even that theory is bunk - one joint doesn’t equal any number of cigarettes, and in fact, may have helpful anti-tumoral properties.  Or you could just take the commonsense approach and consider the hundreds of nasty chemicals pumped into the highly addictive legal cigarettes vs. the non-addictive dried flowers of an organic herb and note the millions who have died from lung cancer and cigarettes vs. the zero that have died from lung cancer and cannabis.