TMIC Sept 2020: The Superheroes Fighting COVID-19: C, D, Zinc (& Cannabis?)

During the COVID-19 multiple wonder drugs have been touted as curing the virus. People keep asking, “Can cannabis cure COVID-19? In this article you’ll learn how to boost your immunity and decrease the likelihood of contracting COVID-19 and learn how cannabis can help with COVID-19 symptoms.

Key Points
  1. Supplementing with vitamins C, D & Zinc can boost your immunity toward COVID-19.
  2. Some of the chemicals in cannabis, and other plants, have antiviral properties.
  3. In Israel scientists are conducting trials on cannabis and COVID-19 to see if cannabis can help treat the virus.

In this video Professor Ian Brightope and Tom Brown discuss COVID-19 immunity, and vitamins C, D and Zinc. Ian also answers the question, “Does cannabis treat COVID-19?”.

Welcome to our third This Month In Cannabis (TMIC) article and episode. TMIC is a monthly series released on the third week of each month where Tom Brown, co-founder of honahlee, discusses important cannabis topics relevant to the Australian market and cannabis community. 

This month in cannabis, we’re talking about a very relevant topic – COVID-19. We’ll cover prevention of the virus and how certain parts of cannabis may be a potential treatment for COVID-19 and other viruses. To help us learn about cannabis and COVID-19, we spoke with Professor Ian Brighthope. Ian is the the founder of Entoura, a medical cannabis manufacturer and cannabis education company.

It’s important to note that there is currently no ‘clinically proven’ evidence that cannabis can help with COVID-19.

If you’d like to jump ahead, here are the topics covered:

Overview of COVID-19

COVID-19 is a virus in the family of coronavirus. COVID-19 is related to the common cold viruses but is a mutation and is far more infectious and dangerous.

COVID-19 penetrates through the nose and makes its way through the bloodstream to the rest of the system. It doesn’t just affect the respiratory tract and the lungs. It has the potential to affect every organ in the body if it gets out of control. As we have seen, it can be a killer virus.

How to reduce the likelihood of contracting COVID-19

First and foremost it’s important to follow the recommendations from the Australian government regarding physical distancing and hygiene.

However, there are some very powerful things we can do to protect ourselves from the virus. Very early in the pandemic, Ian Brighthope started a campaign called “C, D, Zinc”. The goal of the campaign is to inform people of the benefits of supplementing daily with vitamins C, D and Zinc to help strengthen the immune system and reduce our bodies response to the virus. 

Supplementing with C, D and Zinc on a daily basis will strengthen your immune system. It will reduce your body’s response to the virus, boost your immune response that kills the viral cells and will improve the white blood cell’s functionality so that your body can mop up the virus quickly and with limited effects.

Taking these supplements daily will add to your body’s defences from the mucus membranes lining your nose all the way through every cell in the system

Vitamin C, D & Zinc Dosages

Ian Brighthope’s campaign has now been accepted by his colleagues around the world and is backed by the National Institute of Integrative Medicine (NIIM). The recommended daily doses of these supplements are:

  • 4,000 units Vitamin D
  • 4,000 milligrams Vitamin C
  • 40 Milligrams Zinc

It’s important to note that even if you are unable to take these relatively high doses of vitamins, any supplementation may have positive benefits on your health. 

Does smoking (cannabis or tobacco) make you more susceptible to COVID-19?

Ian Brighthope said, “Smoking tobacco, absolutely yes. I’m not so sure about smoking cannabis.” 

Cannabis itself is anti-inflammatory. However, the combustion products of cannabis are well known to have an adverse effect on the lining of the lungs.

Because we want to be protecting the respiratory system during this pandemic, Ian suggests you refrain from smoking anything especially if you have a pre-existing lung or heart condition.

What happens to the body when infected with COVID-19?

When the virus enters the body, it penetrates the mucous membranes lining the nose and lungs and is recognised as a foreign invader. 

White blood cells then take the virus on and attempt to kill it. If the virus is resistant or there’s an excessive load on the system then the white blood cells can start to fail and send messages called cytokines to other cells. These cytokines call for more white blood cells and other cells called T cells and natural killer cells. All of these different cells have specific functions in neutralising the virus.

If all of these cells fail to neutralise the virus then an excessive amount of cytokines build up and get out of control within the body (a cytokine storm). Severely ill patients have an excessive number of cytokines out of control which now also need to be neutralised.

When the immune system can’t manage the cytokine storm or viral infection, the cytokines end up all over the body causing things like organ damage, brain damage and heart damage.

Can cannabis fight COVID-19?

In order to fight COVID-19 we need to find something that will block the entry of the virus into the cells.

There are many antiviral and antibacterial substances found in plants. When talking about cannabis and antiviral chemicals we can talk about:

  • Cannabinoids
  • Terpenes
  • Carotenoids

There are also many other substances in plants that can have antiviral properties. The common cold and other viruses are inhibited by some of these compounds. Unfortunately, we are not certain that any of these compounds have an effect on COVID-19 in particular. 

We do know that scientists are in the process of testing specific cannabis terpenes for their antiviral effects.


THC and COVID-19

While THC does have medicinal benefits, it can also impact our nervous system. Professor Ian Brighthope said, “I’d be very cautious about THC because in these circumstances, we don’t want patients to have any sort of central nervous system inhibition or sedation.”

So, when consuming high THC products or medicine, be mindful that at high doses, they can impact your internal system negatively, like any other chemical.

CBD and COVID-19 

Cannabidiol (CBD) interacts with CB receptors found in the immune system. CBD can be a powerful anti-inflammatory when used in the correct way. While there is limited clinical evidence of CBD down-regulating an overactive immune system, there is a lot of anecdotal and observational evidence. 

CBD isolate has a good safety profile and limited medical contraindications. If you think CBD or cannabis is right for you, please consult a medical professional.

Terpenes and COVID-19

Antibacterial and antiviral substances exist in nearly all plants. Plants too must protect themselves from viruses, bacteria and other invaders. Ian mentioned that many compounds in plants used at the right doses have been proven to inhibit or slow the growth of viruses in a test tube or petri dish. 

Specific terpenes that came in contact with the SARS virus were found to reduce the severity and impact of the virus both in test tubes and in living organisms.

Unfortunately, there isn’t enough research to say which terpenes may help with COVID-19 or many other viruses. 

Cannabis & COVID-19 research

The endocannabinoid system is a major part of our body’s ability to maintain homeostasis or balance. With the contraction of any virus, the virus overwhelms our system and impacts the endocannabinoid system. We also know from decades of use that cannabis has a fairly positive effect on many human conditions because it works on the endocannabinoid system.

When our endocannabinoid system goes out of balance, we need to give it some assistance. To do that, we need a balance of endocannabinoids and potentially terpenes that can help facilitate actions of the naturally occurring cannabinoids in our bodies. 

Scientists are researching cannabis, cannabis terpenes and COVID-19 around the world. Israel has led cannabis research over the last 40 years and is conducting tests in this area. Dedi Meiri, a leading cannabis researcher has already had some promising pre-clinical results using CBD and terpenes to treat COVID-19 symptoms.

While we don’t have clinically proven results just yet, it’s likely there will be much more information available month-by-month in the immediate future.


While there is limited evidence for cannabis as a treatment for COVID-19, the future is promising. There have already been pre-clinical trials in Israel that show promise. We know that CBD is a fairly safe chemical compound and has a number of uses as a medicine.

Whether you’re concerned about contracting COVID-19 or just want to improve your overall health and well-being, supplementing with vitamins C, D and Zinc can help support your immune system.

While cannabis is only legal with a prescription in Australia, for anyone who is experiencing post-viral symptoms such as pain, anxiety or depression, Professor Brighthope suggests that speaking with your GP or other medical specialists about whether medical cannabis might be beneficial for your situation and symptoms.


professor ian brighthope headshot
Prof Ian Brighthope

Professor Ian Brighthope is a retired medical practitioner with over 40 years of experience. Ian has been a pioneer in Australian nutritional and integrative medicine. He’s the founder of Entoura, a medical cannabis manufacturer and educational company.

tom brown author headshot
Tom Brown

Tom is a co-founder of honahlee, startup junkie, a cannabis enthusiast and a digital marketer. His interest in cannabis began as a teenager growing up in New York. Tom loves to trawl through cannabis research, documenting cannabis truths and myths. He started honahlee to help reduce the stigma around cannabis in Australia by educating people about the many uses of the plant.


The team at honahlee are not doctors and are not providing medical advice. Neither Ian Brighthope nor the honahlee team are recommending the use of marijuana (cannabis) for medical or adult use purposes. Cannabis does not work for everyone and may have negative side effects. In Australia, medical marijuana (cannabis) is regulated by the TGA. If you think cannabis is right for you, please consult with your doctor or specialist.