The National Academies of Sciences, Engineering and Medicine released a 440-page page report today that looked at nearly 11,000 cannabis studies. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research is the work of a 32-person committee that included researchers, doctors and educators from across the country. Members include professors from Harvard, Columbia, John Hopkins, Duke and Vanderbilt, and another 15 academics put the findings through an intense peer-review process to ensure the highest standards. Organizations that helped fund the study included the Food and Drug Administration (FDA), Centers for Disease Control and Prevention (CDC), National Cancer Institute and the National Institute on Drug Abuse (NIDA). In other words, this massive report is a big deal, and it could play a major role in determining the schedule status of cannabis in the near future.
Statement of Task
Per the preface, “The committee will develop a consensus report with two primary sections: (1) a section of the report will summarize what can be determined about the health effects of marijuana use and, (2) a section of the report will summarize potential therapeutic uses of marijuana.” The primary goal was to determine what we know and don’t know, both of which are far more substantial than most people think, and to identify research questions the medical community could realistically answer in the next three years. The report came to nearly 100 conclusions that it divided into “weight-of-evidence” categories, which include conclusive (strong evidence with no credible opposition), substantial (strong evidence with minor limitations), moderate (some evidence from good- to fair-quality studies), limited (weak evidence) and no/insufficient (not enough evidence to draw conclusions). Clearly the most conclusive statement the committee made was that more research needed to be done and that government restrictions on research are so excessively burdensome that they constitute a “public health problem.”
Findings: Benefits of Cannabis
The report identifies three health conditions for which cannabis clearly provides medical benefits: chronic pain, multiple sclerosis (MS)-related muscle spasms and chemotherapy-induced nausea and vomiting. Chronic pain was identified as the “most common” reason people requested medical cannabis. The study also found moderate evidence that suggests cannabis improves “short-term sleep outcomes in individuals with sleep disturbance associated with obstructive sleep apnea syndrome, fibromyalgia, chronic pain, and multiple sclerosis.” Interestingly, moderate evidence also exists that acute (but not chronic) use can improve airway dynamics in the respiratory system.
Limited evidence suggests cannabis helps with several other conditions, including weight management associated with HIV/AIDS, Tourette’s syndrome, social anxiety disorders, metabolic syndrome, post-traumatic stress disorder (PTSD) and recovery outcomes from traumatic brain injury or intracranial hemorrhage. Cannabis may also provide anti-inflammatory benefits.
Conversely, the study said there is limited evidence that cannabis does not help with dementia, glaucoma or depression associated with chronic pain or MS. Likewise, the researchers said not enough evidence exists to determine the benefits (or lack thereof) in treating cancer, epilepsy, amyotrophic lateral sclerosis, Huntington’s disease, Parkinson’s disease, dystonia and addiction recovery. However, this does not mean cannabis does or does not help these conditions, but rather that more top-quality studies are necessary. For example, the report cited a 2016 study on pediatric epilepsy in which the majority of kids given a CBD/THC (20:1) formulation saw their seizure frequency drop by 50 to 100 percent, but the committee discounted the finding because it lacked a concurrent placebo control group and evidence that the improvements did not regress.
Findings: The Risks of Cannabis
This is the point where it is important to note that correlation does not imply causation, meaning that an association between cannabis and certain health risks is not the same as cause-and-effect. That said, the committee did find evidence of potential risk.
The Health Effects of Cannabis and Cannabinoids found substantial evidence that cannabis is associated with an increased risk of motor vehicle crashes and developing schizophrenia and other psychoses. Likewise, smoking while pregnant appears to be a risk factor for lower birth weight, and chronic smokers may experience increased risk for respiratory problems and chronic bronchitis. Moderate evidence suggests cannabis might be a risk factor for social anxiety, substance abuse problems (e.g., alcohol, hard drugs) and cognitive impairment, though cannabis consumers who suffer from psychosis actually show better cognitive performance.
The study also found limited evidence that chronic cannabis use is associated with higher rates of non-seminoma-type testicular germ cell tumors, better known as cancer in your balls, but this risk placed in the weakest evidence category represents the only link found between cannabis and cancer risk. Instead, moderate evidence shows no connection between cannabis and cancer in the lungs, head and neck, and there is no evidence either way for the other common forms of cancer. Likewise, limited evidence suggests smoking cannabis is associated with triggering a heart attack and stroke, but there is insufficient evidence to suggest that cannabis increases or decreases the risk of a heart attack.
Highlighting the difficulties in assessing cannabis-related risk, the report found limited evidence that cannabis decreases the risk of diabetes but increases the risk of prediabetes. Similar contradictory findings occurred with social anxiety.
Major Conclusion: The Government = The Problem
The Health Effects of Cannabis and Cannabinoids noted, very importantly, that studies often rely on “less sophisticated approaches” that result in “an overestimation of the association between cannabis use and negative social outcomes.” Moreover, finding statistical associations between cannabis and an increased risk is a long, long way from saying cannabis caused the risk or the disorder. Arguably the strongest conclusion coming from the study was that researchers have very limited insight into the effects of cannabis, and the government is to blame.
“Despite these changes in state policy… the federal government has not legalized cannabis and continues to enforce restrictive policies and regulations on research into the health benefits or harms of cannabis products that are available to consumers in a majority of states,” said the report. “These policies and regulations may impose barriers to conducting research on the health effects of cannabis and cannabinoids has been limited in the United States, leaving patients, health care professionals, and policy makers without the evidence they need to make sound decisions regarding the use of cannabis and cannabinoids. This lack of evidence-based information on the health effects of cannabis and cannabinoids poses a public health risk.”
The report then spends several pages documenting all the restrictions the government puts on cannabis research, especially studies on the potential therapeutic benefits. In fact, researchers must procure cannabis from NIDA for clinical studies, and more than 80 percent of the cannabis studies funded by NIDA in 2015 focused on the potential negative outcomes. Worse still, NIDA is just one of many bureaucratic hurdles a person must overcome to obtain all the necessary approvals. “This process can be a daunting experience for researchers,” stated the report, which then cited studies that suggest the extreme government regulation on cannabis studies actually suppresses research. Though not expressly stated, the committee seemed to want cannabis classified as no higher than a Schedule III substance.
What was the final conclusion? Here it is in full: “The methodological challenges and the regulatory, financial, and access barriers described above markedly affect the ability to conduct comprehensive basic, clinical, and public health research on the health effects of cannabis use, with further consequences for the many potential beneficiaries of such research. In the absence of an appropriately funded and supported cannabis research agenda, patients may be unaware of viable treatment options, providers may be unable to prescribe effective treatments, policy makers may be hindered from developing evidence-based policies, and health care organizations and insurance providers lack a basis on which to revise their care and coverage policies. In short, such barriers represent a public health problem.”
In other words, the government can talk about all the unfounded health risks it associates with cannabis, but the experts seem to suggest the government is causing the real health problem by stopping the medical community from finding real answers.