For both the general public as well as the scientific community the interest in CBD has grown immensely over the past years. Figure 1 shows the number of publications that contain the word ‘cannabidiol’ on PubMed (a database focused on medical research articles) as of May 2020, as a function of publication year. We see that starting in the 2000s the amount of publications on CBD has increased exponentially. Not even half-way into 2020 we see that there are already over 300 published articles, which means that by the end of the year that will probably mean over 600 publications on CBD alone will be published.
At Becanex we are very interested in the evolution of scientific knowledge concerning CBD and other cannabinoids. In this new blog series we want to share some of the more recent, and interesting scientific findings. In each blog we will highlight a different scientific paper or a different cannabinoid, and present the information in a readable and (hopefully!) interesting way. We hope that this way we can share some of our enthusiasm about cannabinoids and hemp extracts with all of you!
For thisfirst blog in the series we want to start by discussing some of the scientific terminology that is used in medical research. Scientists have a specific vocabulary, where things might not mean the same as during a normal conversation. To ensure that the information we convey here is clear, a small primer on terminology is useful.
Additionally, we will quickly highlight some of the most promising results for cannabinoids at the moment. We should note that most scientific research into cannabinoids at the moment focuses on specific health problems (or so-called therapeutic effects). There is some general research into the broader effects of cannabinoids, mostly focused on the immune system and inflammation, but this is very much a still developing field. Most the results that follow are based on a report from 2017 by the National Academy of Sciences, Engineering and Medicine (The Health Effects of Cannabis and Cannabinoids: The Current State ofEvidence and Recommendations for Research, available at http://nap.edu/24625). This almost 500 page book provides an in-depth look into the state of science surrounding cannabinoids, and we feel it serves as a nice starting-point for this blog series.
In medical science it is common to divide scientific findings into certain categories. Depending on the type of research that was done, how rigorous it was and a range of other parameters these scientific findings (or ‘evidence’) can be classified as ‘conclusive/substantial’, ‘moderate’, ‘limited’ or ‘insufficient’. So what does this mean? We will use a simplified example to clarify the situation. Imagine that there are two research groups, both looking into the effects of CBD on cancer proliferation. One of the groups does a lot of testing on various cancer cell lines that simulate a lot of different types of cancer (so-calledin vitro work). This group finds very clear evidence that CBD has a big effect on the proliferation of cancer in all these cell lines, suggesting that CBD would be efficient as an anti-cancer agent. The other research group takes a different approach, they use a group of people suffering from a specific type of cancer and perform a so-called double blind trial, where part of the patients are given CBD, while the other patients are given a placebo. In the end they find that there is some effect of CBD on the life expectancy of these patients, but the effect seems small.
Clearly, these two research groups find differing results (large effect on everything versus small effect on a specific type of cancer). Which ‘evidence’ now carries the largest weight? In medical science these double-blind trials are considered the ‘holy grail’ of scientific evidence. So someone reviewing the state of science around CBD and cancer would assign the second research groups’ evidence a much bigger weight, compared to the in-vitro work performed by the first group. So based on this, the reviewer might say that there is moderate evidence that CBD could have a small positive effect. The reviewer places more ‘trust’ in the second study, due to it being a double-blind trial performed on humans, compared to the cell-lines used in the in-vitro study.
Additionally, in science in general, and medical science in particular, the rule is that findings need to be repeated. One positive finding has less weight than 10 positive findings. If we go back to the example given above, if another independent research group would also perform a double-blind trial with patients, and find similar results, this would increase the quality, or weight of the total evidence. Based on this, a reviewer might now say that there is substantial evidence, compared to moderate evidence when it was only a single study.
Of course, this example is very simplified and the reality is a lot more complex, but hopefully it illustrates the concept of these different categories of evidence. So how is the evidence for positive effects for cannabis and CBD categorized at the moment? Currently there is:
· that CBD can serve to reduce nausea and vomiting for chemotherapy patients,
· that cannabis can help in the treatment of chronic pain,
· and that CBD can improve the quality of life for multiple sclerosis patients due toless spasticity symptoms.
· that cannabinoids can improve sleep quality for people who have sleep disturbances associated with some serious illnesses.
· that CBD helps with anxiety symptoms when suffering from social anxiety disorders, and that it might help with PTSD
Besides such positive evidence, a part of scientific research is also finding out that something does not work. For instance, there is currently limited evidence that cannabinoids are ineffective to improve symptoms associated with dementia.
This list is not exhaustive (for a complete list we refer to the above referenced document). However, it does show that the possibilities for cannabinoids stretch very different medical fields, ranging from pain, to sleep, nausea, and anxiety. It also shows that the science into cannabinoids is still very much developing, and that there are very exciting times ahead of us!
In upcoming blogs we will take a deep dive into several of these exciting possibilities for cannabinoids, as well as focus on specific cannabinoids and their (medical) uses. At Becanex we are always following the current science, and we are very much looking forward to share our enthusiasm about the fascinating world of cannabinoids with as many people as possible!