Cannabis Research: What Does Science Tell Us about Cannabis

Cannabis Research: What Does Science Tell Us about Cannabis

For years, people have referred to Cannabis as a drug. However, cannabis has actually been used for over 3,000 years as a medicine.

And, recent studies are showing that cannabis can actually aid in the treatment of many ailments.

Today, not only are people seeing the benefits of the whole plant cannabis, but we are now discovering the different cannabinoids such as cannabidiol that can be extracted.

Science has come a long way in finding out everything there is to know about cannabis. So, here is everything you need to know about cannabis and what science tells us!

What is Cannabis?

Cannabis is typically what people refer to as marijuana. Cannabis originally comes from Indian hemp plants such as Cannabis sativa and Cannabis indica.

The main ingredient in a marijuana plant is THC. However, there are industrial hemp cannabis plants that have a higher CBD content.

Cannabis is considered a depressant drug. However, it does not make you feel depressed. Instead, it slows down the activity in your central nervous system.

This means it slows messages going between the brain and the body. When this happens, it can affect many areas in the body.

How Does it Work?

Before we really understood cannabis, we knew about THC. THC is one of over 100 cannabinoids that are found in cannabis plants.

Researchers wanted to know how how THC worked and if our own bodies produced anything similar to it.

This is how we found out about a system in our bodies called the Endocannabinoid system.

This system was discovered by Dr. L.A. Matsuda in the 1990s. He was the first person to describe the functional expression and structure of of a cannabinoid receptor in the body.

As he delved into THC and how it worked in our body, he discovered a complex network of cannabinoid receptors in cells and through the central and peripheral nervous system.

So, our body creates its own cannabinoid compounds that then bind to these receptors. Cannabinoid compounds are a diverse class of chemical compounds.

These chemical compounds are found in the human body and in cannabis plants. Cannabinoids found in cannabis plants are called phytocannabinoids. 

There are more than 100 phytocannabinoids found in the cannabis plant. The two that closely resemble our own bodies’ are THC and CBD.

The chemical compounds found in the human body are called endocannabinoids. These are:

  • 2-Arachidonoylglycerol (2-AG)
  • Anandamide

    When are bodies receptors are exposed to the cannabinoids, the cannabinoids bind to the receptors.

    There are two main cannabinoid receptors that can send messages to the rest of the body. These are CB1 and CB2.

    The CB1 receptors can be found in the brain, nervous system, the intestines, connective tissue, gonads and other glands throughout the body.

    When the CB1 receptor is activated, it sends messages throughout the body that can:

    • Relieve depression
    • Lower blood pressure
    • Decrease intestinal problems
    • Increase brain-derived neurotrophic factors (learning, working memory, and higher thinking)
    • Lower anxiety
    • Reduce fear

    When CB2 receptors are activated by cannabinoids, they send messages to the body that can help the following ailments:

    • Cardiovascular problems
    • Gastrointestinal problems
    • Neurodegenerative problems
    • Psychiatric problems
    • Autoimmune diseases
    • Kidney issues
    • Bone and skin health
    • Cancer

      Where Can You Find Evidence of Cannabis?

      As with any medicine, it is important to do your research. As you can see above, cannabis can be a medicinal benefit to various ailments.

      However, it is always important to look into the evidence of how cannabis works in the body for each ailment.

      You can find evidence of what cannabis can and cannot do by looking at published trials and studies on PubMed which is also known as the National Center for Biotechnological Information.

      Some of the Evidence and Research

      Not only can you find evidence on PubMed, but various other countries including Canada, Europe, and Israel have also conducted cannabis studies. 

      Here is just some of the evidence we have about cannabis:

      #1 It has proven anti-inflammatory and neuroprotective properties

      We know that inflammation plays a major role in Alzheimer’s, fine motor, Parkinson’s, AIDS, dementia, multiple sclerosis, autism, and schizophrenia.

      Therefore, there has been a lot of research done on the use of cannabis to delay the onset of these diseases.

      You can find some of these studies below:

      1. The potential therapeutic effects of THC on Alzheimer’s Disease:Low doses of THC can enhance the mitochondria function. This data strongly suggests THC could be a potential therapeutic treatment option for Alzheimer’s.”
      2. Cannabinoids as antioxidants and neuroprotectants: “Cannabinoids have been found to have antioxidant properties….This makes them useful in treatment of prophylaxis of a variety of diseases such as ischemic, age related, inflammatory, and autoimmune.
      3. A Molecular Link Between the Active Component of Marijuana and Alzheimer’s Disease: Cannabinoid molecules may directly impact the progression of this debilitating disease.”

        #2 It May Help with Cancer

        Chemical compounds found in cannabis plants have been found to decrease cancer growth by inhibiting cells from continuing to grow automatically.

        Basically, cannabis puts the cancer cells back into homeostasis in which they grow, divide, and die like they should.

        Majority of research involved around cannabis and cancer is how it helps alleviate the symptoms associated with cancer treatments such as nausea and loss of appetite.

        You can find some of the cancer research below:

        1. Cannabinoids and cancer: “There is accumulating evidence that they (cannabinoids) could also be useful for the inhibition of tumour cell growth by modulating key survival signalling pathways.”
        2. Cannabinoids for Cancer Treatment: Progress and Promise: “Although the observed effects of cannabinoids are complex and sometimes contradictory, there is overwhelming evidence to suggest that cannabinoids can be explored as chemotherapeutic agents for the treatment of cancer.”
        3. Cannabidiol Induces Programmed Cell Death in Breast Cancer Cells by Coordinating the Cross-talk between Apoptosis and Autophagy: “CBD induces concentration-dependent cell death in breast cancer cell lines in a receptor-independent manner.”

          #3 It Alleviates Chronic Pain

          One of the most well-known reasons people use cannabis is to combat chronic pain. Cannabis has been found to help neuropathic pain in which other medication doesn’t.

          There is a lot of quality studies and evidence including clinical trials that demonstrate the efficacy as well as the safety of cannabis and treating chronic pain.

          Below are just a few of the studies:

          1. Marijuana and Pain:Peripheral nerves that detect pain sensations contain abundant receptors for cannabinoids, and cannabinoids appear to block peripheral nerve pain in experimental animals.”
          2. Cannabis and Cannabinoids for treatment of Chronic Pain: “It seems unlikely that cannabinoids are highly effective medicines for CNCP.”
          3. Clinical Trials: “Listed, you will find links to papers and conference presentations on clinical trials with cannabis or cannabinoids.”

            #4 It May Help Crohn's Disease

            Many people have found the use of cannabis helps Crohn’s disease, ulcerative colitis, and other forms of inflammatory bowel disease.

            In fact, recent trials have shown that 50% of Crohn’s patients had complete remission when using cannabis. And, 90% of patients at least achieved some improvement.

            Here are a few studies you can take a look at:

            1. Impact of Cannabis Treatment on the Quality of Life, Weight and Clinical Disease Activity in Inflammatory Bowel Disease Patients: A Pilot Prospective Study.
            2. Cannabis Induces Clinical Response in Patients with Crohn’s: “Cannabis provided a significantly higher rate of clinical response without any alarming side effects.”
            3. Therapeutic Use of Cannabis in Inflammatory Bowel Disease:A significant portion of IBD patients, particularly those with severe disease, use cannabis to relieve symptoms of pain, nausea, and appetite and to improve their overall mood.”

              Medical Reasons for Using Marijuana

              Because of the scientific research of cannabis, many states throughout the U.S. have legalized cannabis known as marijuana for medicinal purposes.

              However, those who wish to use marijuana medicinally must have qualifying conditions in order to receive medical marijuana. These conditions are determined by each state.

              However, some of the most well-known conditions include:

              • Epilepsy and other seizures
              • Crohn’s disease
              • Chronic pain
              • Severe nausea
              • Post Traumatic Stress Disorder
              • Glaucoma
              • HIV/AIDS
              • Cancer

              If you are unsure as to whether your condition qualifies for medical cannabis in your state, you can check out the laws on Leafly.

              Side Effects and Risks

              Although research has found many great benefits to the medicinal use of cannabis, it is not without side effects.

              Here are just a few of the side effects of cannabis:

              Not good for lungs: Evidence from smoking or vaping cannabis is weak when compared to tobacco, putting anything into your lungs that isn’t meant to be there could damage them.

              Can cause psychosis: However, there is a correlation of cannabis and psychosis that is well documented. This correlation is usually seen with the recreational use of cannabis at a young age.

              Can cause depression and anxiety: Regular marijuana use is associated with increased risk of anxiety and depression. High THC concentration can increase anxiety

              Altars judgement: Using cannabis recreational can cause you to make unsound judgments you wouldn’t normally make.

              Could lead to addiction: Although this is rare, many see cannabis as a gateway drug.

              Here are some of the more common side effects:

              • Dry mouth
              • Nausea
              • Vomiting
              • Dry or red eyes
              • Heart and blood pressure problems
              • Lung problems
              • Impaired mental functioning
              • A headache
              • Dizziness
              • Numbness
              • Panic
              • Hallucinations
              • Flashbacks
              • Depression
              • Sexual problems

                However, when these side effects are compared to the effects and risks of pharmaceuticals, the risk involved in cannabis use is low.

                Therefore, cannabis side effects and risks should be compared to prescription medications such as anti-psychotics, opiods, NSAIDS, and anti-epileptics.

                The FDA and Cannabis

                Another thing to consider when doing your research of cannabis is the FDA. Although people have used marijuana for over 3,000 years, the FDA has not regulated it.

                In fact, the FDA has only recently regulated individual components of marijuana or similar synthetic substances.

                The U.S. Food and Drug Administration also known as the FDA has not approved marijuana for treating any health problems.

                They have, however, approved three cannabinoids as drugs. In 2018, a solution called Epidiolex was approved as a drug for the treatment of seizures associated with two rare forms of epilepsy.

                Epidiolex is derived from cannabis plants. It is actually a specific cannabinoid that has been extracted from the cannabis plant called cannibidiol or CBD.

                The FDA has also approved synthetic cannabinoids called Dronabinol and Nabilone. These ar used to treat nausea and vomiting associated with cancer chemotherapy.

                Dronabinal also contains a synthetic delta-9tetrahydrocannabinol (THC). Therefore, it is also used to treat loss of appetite and weight loss in people with AIDS.

                Furthermore, the FDA has decided that it is not legal to sell products that contain THC or CBD as dietary supplements. It is not legal to sell foods containing added THC or CBD.

                However, certain states as well as the District of Columbia have allowed the use of cannabis for specific purposes.

                Cannabinoids Instead of Cannabis

                Because the FDA has not approved cannabis at this time, and only states are approving cannabis such as marijuana, many have turned to cannabinoids instead.

                Although there still is not a lot of knowledge about all the cannabinoids that exist, we do know a lot about one in particular.

                Cannabidiol known as CBD is hitting the market in storm. It is a cannabinoid found in cannabis plants.

                The FDA and federal government still see cannabis as a drug because of the psychoactive component of cannabis known as THC.

                However, CBD does not have the same effect as THC does when used. But should you use CBD instead of the full cannabis plant?

                This question greatly depends on the legality in your state. All, but 4 states have legalized CBD, but only 33 states have legalized medical cannabis.

                Like the full plant cannabis, CBD has benefits and side effects.

                Benefits of CBD

                Through research, that can be found at the National Center for Biotechnology Information, we have discovered many benefits of using CBD. Here are a few of the benefits:

                • Epilepsy: Have you heard of Charlotte? 85% of parents who used CBD for their child claimed it reduced their seizures.
                • Pain Relief: Many people have had reduced pain from using CBD, religiously.
                • Neurological disorders:
                • Cancer: Not only is cancer a great anti nausea treatment, but research suggests it may also have anti cancer properties.
                • Anxiety and Depression: Unlike marijuana that could increase anxiety, CBD actually reduces it.

                There are many other benefits of CBD that have yet to be tested. So, it is always important to do your own research.

                Side Effects of CBD

                Likewise, with any drug there are some side effects that have been discussed. It is also important to note that CBD doesn’t work for everyone. Here are some of the side effects:

                • The FDA doesn’t regulate CBD. This means you may not be getting an accurate amount.
                • CBD is known to interact with other medications.
                • Smoking CBD can be risky. Smoking anything directly affects your lungs and creates build up.
                • Allergic reaction. Some people are actually allergic to cannabis plants.
                • Dry mouth. Many people have reported a dry mouth after CBD use.
                • Tiredness. Due to alleviating stress hormones, CBD can cause tiredness.
                • Anxiety. This is only found in extremely high doses of CBD.  
                • Interferes with the reward system. When combined with THC, CBD can interfere with the bodies motivation and reward system.

                If you find that CBD isn’t working for you, you can try adjusting dosage you are taking. You can also adjust the times of day you take it.

                Here is What to Do if You Don’t feel the benefits of CBD.


                There is a lot of scientific evidence that both support cannabis as well as those that tout it as being a drug. The best way to know for sure is to do your own research.

                Cannabis isn’t for everyone, but it does have many medicinal benefits that are worth noting. If you still have questions about cannabis, you can speak to a cannabis doctor.

                These doctors are knowledgeable on cannabis as well as cannabinoids and specifically CBD. If you would like to speak to a doctor, you can find a doctor in your area on Leafly.

                Keep in mind, cannabis even as a medicine is not legal in all 50 states. Whether you are looking into using CBD or the whole plant cannabis, you will need to check the legality in your state.


                1. Figure 2f from: Irimia R, Gottschling M (2016) Taxonomic revision of Rochefortia Sw. (Ehretiaceae, Boraginales). Biodiversity Data Journal 4: E7720. (n.d.). doi:10.3897/bdj.4.e7720.figure2f.
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                4. Home. (n.d.). Retrieved from
                5. Kaplan, J. (2018, January 19). The Top Medical Cannabis Studies of 2017. Retrieved from

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