A new report from the National Academies of Sciences, Engineering, and Medicine offers a demanding review of scientific research published since 1999 about what is known about the health impressions of cannabis and cannabis by products - such as marijuana and active chemical composites known as cannabinoids - ranging from their beneficial effects to their risks for causing certain cancers, diseases, mental health disorders, and injuries. The commission that carried out the study and wrote the report carefully measured more than 10,000 scientific summaries to reach its nearly 100 conclusions. The committee also wished-for ways to expand and advances the quality of cannabis research efforts, enhance data collection efforts to support the advancement of research, and address the current barriers to cannabis research.

Marijuana Landscape Evolving To Be Considered As A Medical Intervention

"For centuries, the landscape of marijuana use has been shifting as increasingly more states are authorizing cannabis for the treatment of medical conditions and frivolous use," said Marie McCormick, chair of the committee; the Sumner and Esther Feldberg Professor of Maternal and Child Health, department of social and behavioral sciences, Harvard T.H. Chan School of Public Health; and professor of pediatrics, Harvard Medical School, Cambridge, Mass. "This increasing acceptance, convenience, and use of cannabis and its byproducts have raised important public health anxieties. Moreover, the lack of any aggregated knowledge of cannabis-related health effects has led to hesitation about what, if any, are the harms or benefits from its use. As laws and policies remain to change, research must also."

Therapeutic Effects

One of the therapeutic uses is to treat chronic pain on adults. The committee found indication to support that patients who were treated with cannabis or cannabinoids were more likely to yield a significant decrease in pain symptoms. For adults with multiple sclerosis-related muscle shudders, there was substantial evidence that short-term use of certain "oral cannabinoids" - man-made, cannabinoid-based medicines that are orally consumed - improved their reported symptoms. Also, in adults with chemotherapy-induced nausea and vomiting, there was decisive indication that certain oral cannabinoids were actual fact in preventing and treating those ailments.

Cancer

Regarding the link amongst marijuana and cancer, the committee found suggestion that mark smoking cannabis does not increase the risk for cancers often related with tobacco use - such as lung and head and neck cancers. The committee also found limited indication that cannabis use is linked with one sub-type of testicular cancer and inadequate evidence that cannabis use by a mother or father during pregnancy leads to a more risk of cancers in the child.

Heart Attack, Stroke, and Diabetes

The committee said that more research is needed to regulate whether and how cannabis use relates to heart attack, stroke, and diabetes. Nevertheless, some evidence suggests that cannabis smoking also trigger a heart attack.

Respiratory Disease

The evidence reviewed by the committee proposes that smoking cannabis on a regular basis is linked with more frequent chronic bronchitis episodes and worse the respiratory symptoms, such as chronic cough and phlegm creation, but quitting cannabis smoking is more likely to reduce these settings. The committee stated that it is uncertain whether cannabis use is associated with certain respiratory diseases, including chronic obstructive pulmonary disease, asthma, or worsened lung function.

Immunity

There is a lack of data on the effects of cannabis or cannabinoid-based therapeutics on the human immune system, as well as deficient data to draw overarching conclusions about the effects of cannabis smoke or cannabinoids on immune capability, the committee stated. There is also unsatisfactory evidence to support or refute a numerical association between cannabis or cannabinoid use and adverse effects on immune status in persons with HIV. Still, limited evidence suggests that regular contact to cannabis smoke may have anti-inflammatory activity.

Mental Health

The evidence studied by the committee suggests that cannabis use is likely to growth the risk of developing schizophrenia, other psychoses, and anxiety disorders, and to a lesser extent depression. Alternatively, in individuals with schizophrenia and other psychoses, a history of cannabis use may be linked to better recital on learning and memory tasks. Heavy cannabis users are more likely to report thoughts of suicide than non-users, and in individuals with bipolar disorder, near-daily cannabis users show augmented symptoms of the disorder than non-users.

Prenatal, Perinatal, And Neonatal Exposure

Smoking cannabis during pregnancy is linked to lower birth weight in the progeny, some data suggests. Yet, the relationship with other pregnancy and childhood conclusions is unclear.

Challenges And Barriers In Conducting Cannabis Research

In addition to acclaiming more research on the beneficial and harmful effects of cannabis and cannabinoid use, the committee highlighted several challenges and barriers in leading such research. For instance, specific regulatory barriers, including the classification of cannabis as a Schedule I element, impede the advancement of research. Academics also often find it difficult to gain access to the measure, quality, and type of cannabis product essential to address specific research questions. The committee said a various network of funders is desirable to support cannabis and cannabinoid research.