This is also not surprising since the total amount of smoke ingested by users of both products is likely to be much greater than that ingested by respondents who smoke only marijuana.Tobacco and marijuana are similar in many respects so that the damage that these two products cause can be compared. Table 7 shows the proportion of explained variation that is due to tobacco and marijuana use for the age group 15 – 24. The first row in this table gives the values of the ln-likelihood function at baseline; that is when no regressors are used. The next rows display the ln-likelihood function as groups of regressors are added as explanatory variables. First demographic variables are included, then smoking variables, and finally the variables representing marijuana use. The proportion of the explained variation due to smoking is 62.2% and 66.1% for males and females,respectively. However, the proportions explained by marijuana use are much smaller at7.1% and 21.3% so marijuana use as a factor in self-reported physica health is much less important that tobacco use.
It should also be noted that in addition to the larger proportion of explained variation, which due to marijuana use it is also the case that both self-reported health measures are higher among regular marijuana users than for daily smokers. This result also holds for self-reported mental healthy though the difference between the effects of two substances is not nearly as great. This is not so surprising as it may appear; there is a literature, which deals with smoking and mental problems.Depression, anxiety, schizophrenia have been linked to cigarette smoking.Summarizing what we have found, the major health issue involving marijuana concerns teenagers and adolescents. It starts with this age group and often ends with it. Individuals who do not use marijuana before the age of 21 almost never use it. Its use is also more likely to be associated with males. Like most other researchers who have examined the health consequences of marijuana use, we find harmful effects on both physical and mental health that are persistent even if respondents are no longer users.The impression portrayed by the literature is that early and continued significant use is what matters.
Our results are consistent with these findings but are much less favorable towards marijuana use. It seems that given existing use habits of Canadian teenagers if they start using earlier than the age of 15 they will suffer for the rest of their lives even if they never use marijuana after the age of 21. On a more positive note we found that marijuana use explained less of the variation in self-reported health than that attributable to smoking tobacco for the age group 15 – 24, in spite of the fact that there more marijuana users than tobacco users in this age group. Male marijuana users under the age of 21 were almost 3 times as numerous as tobacco users. Marijuana is damaging health-wise but not as damaging as teenage tobacco smoking, the consequences of which as a society we have been able to manage.It would also seem that the likelihood of an epidemic of health problems emerging out of new marijuana regulations could be dramatically reduced if extensive educational programs in schools accompany legalization. Data from the 2012 Canadian Alcohol and Drug Use Monitoring Survey show that only five percent of respondents below the age of 21 think that regular use of marijuana is a health hazard. If this age group were better informed about the risks of cognitive impairment and psychological damage that arise with adolescent marijuana use its members might be less inclined to be users.
Anti-smoking campaigns have been very successful in reducing tobacco use among elementary and high school students. This shows up in our data as a lower rate of tobacco use. It is possible that marijuana usage could be also reduced in this age group if more information is made available.The implication for drug policy that comes from these results is that marijuana legalization should be facilitated through a set of institutional arrangements which limit access to marijuana for all individuals under the age of 18. Adolescents need to be encouraged not to use marijuana and strict government control over its production and distribution is needed to protect them. Price, THC content, and advertising also have to be regulated. At a more general level public policy should promote caution and awareness of the harmful consequences of marijuana use. Data from a total of 43 marijuana smokers and 22 non-smokers were used in this study. None of these 65 individuals reported smoking tobacco products. Due to the novelty of this work, subjects were not restricted based on body mass index or dietary intake. That said, individuals who were using certain medications which are known to impact the outcome measures of the investigation were excluded. Subjects were recruited into the study through the use of flyers and online announcements.