as a medical professional i can say your both wrong.. or right.. however you wanna look at it

the body needs certain protiens and acids that are in meat... thats not to say that these can't be replaced by meat free substitutes.. plenty of people don't eat meat and are perfectly healthy, most of them however do not know how to properly balance a meat free diet and are not healthy

its true that cannabis seed is the most nutritionally complete natural food source, and it does contain many protiens and efa's that are crucial for a non meat diet.... and smoking it dramatically increases melatonin production, but it is hardly a key to immortality

so melatonin has been shown to fight cancer and extend lifespan... so what?? it is only effective when taken properly, that is just a little before bed... so smoking pot all day really doesn't provide many benefits from melatonin at all

and the sketchy at best research has shown it to increase lifespan by as much as 20%... thats not even remotely close to 200 years... i dont care how healthy you eat, its gonna take alot more than diet to have a long life, not to mention an unnaturally long one

Im starting to think (but not confirmed yet) that your either incredibly young , incredibly naive or just playing with us....
my vote goes for #1 and 3