Marijuana is 10 times more potent than it was in the sixties, so it is more dangerous

   This is another misleading drug myth, but is also very simple to understand. First of all, no statistics show that marijuana is any more potent than it used to be. The Cannabis plant has much more history on planet earth than humans do, and we have not revolutionized its cultivation since our discovery of its magnificent properties. Hash, the condensed sensimila and THC of Marijuana has been around for thousands of years. Even if we one day are capable of breeding a "Super-Weed" with THC content above 20 or 30%, this will not affect the dangers concerning the smoking of marijuana.

Experienced pot smokers have a system of auto-titration, or basically smoking until they are satisfied. Some smokers will just smoke until they have none left. Either way, the more THC there is in the marijuana being smoked, the less the user will have to smoke to achieve the same high. This means that stronger marijuana is healthier. And the LD 50, or average lethal dose, is so incredibly high that the marijuana smoker will never die because of marijuana intoxication.

Sources:

1. Internet FAQ Archives, (2004), Cannabis/Marijuana FAQ, http://www.slate.com/id/2074151/

2. http://paranoia.lycaeum.org/marijuana/facts/mj-health-mythology.html#myth11

3. http://www.faqs.org/faqs/drugs/hemp-marijuana/