Lockdown is over; winter is here. As the temperature drops in the UK, cases of common colds, bugs and flu are on the rise. It seems the entire nation is battling a severe case of the sniffles, after months of being stuck indoors, our immune systems appear to be weaker than ever before.
Every day, we come into contact with thousands of bacteria. Not all of these microbes are nasty. In fact, they actually help to keep us healthy, as our body needs to be exposed to germs for it to build up an effective defence system.
But, with lockdown, many of us have spent a sizeable chunk of our year at home. For a long time, rules have been in place to remain safe and sanitary. We haven’t really been coming across many germs, which hasn’t exactly been the best for our immune system.
So it seems as though our immune systems are in need of a little boost. For years, scientists have been investigating the best natural ways to support our immune function- but could CBD be the answer?
Endocannabinoids & the immune system
The immune system is our body’s defence mechanism. It strives to keep us safe by fighting off bacteria, viruses, and other biological threats. Without our immune system, these invaders- which we encounter every day- would be deadly.
Immune cells are responsible for recognising foreign bodies. They can be split into two categories: phagocytes, which engulf and break down invaders, and lymphocytes, which learn to recognise invaders in order to swiftly destroy them in future.
Each component of the immune system has a precise role. With a vast array of functions, immune cells and mediators need to be well-orchestrated- and the system that helps to maintain this balance? The endocannabinoid system (ECS).
The ECS helps to regulate our mood, appetite, sleep, memory, and much more. As the ‘gatekeeper’ of the immune system, the ECS oversees immune activity, aiming to keep it stable and balanced- or in a state of homeostasis. It does this through the activity of cannabinoid receptors, CB1 and CB2, which can be found all over the immune system.
With the ECS and the immune system being so highly interconnected, this opens the possibility of using cannabinoids to modulate immune activity. One compound known to assist the ECS in its biological endeavours is CBD.
What is CBD?
Cannabidiol- more commonly known as CBD- is an active compound from the Cannabis sativa plant. It is a non-psychoactive cannabinoid, meaning it interacts with our ECS without inducing the ‘high’ that is commonly associated with cannabis.
The mind-altering effects of cannabis are down to a compound called tetrahydrocannabinol (THC). For a CBD product to be sold in the UK, it must contain negligible amounts of THC- so, yes, CBD is completely legal.
CBD’s therapeutic potential has been extensively studied; it is an accepted treatment for rare forms of epilepsy and shows promise in the treatment of anxiety, sleep disorders, chronic pain, and much more.
The seemingly endless benefits of CBD are down to its ability to alter activity in the ECS. So, CBD can also have a knock-on effect on immune cell activity.
How does CBD affect the immune system?
Most of the research into CBD and the immune system has looked exclusively at inflammation and autoimmune disease. There is little evidence to say whether or not CBD can boost our immune system- but hold on, we’ll go over that in a bit.
CBD is known to be anti-inflammatory. In numerous animal models and human studies, CBD inhibits the onset of inflammation and reduces the severity of inflammatory disease. This is because CBD reduces levels of pro-inflammatory cytokines, the molecules responsible for telling the body to initiate an immune response.
Occasionally, the body can mistakenly deem its own cells dangerous and the immune system begins to attack itself. This is known as an autoimmune disease. Common autoimmune conditions include type 1 diabetes, rheumatoid arthritis, lupus, psoriasis, and multiple sclerosis (MS).
CBD has also been shown to be immunosuppressive in diseases characterised by uncontrollable immune activity. For example, in studies of experimental autoimmune encephalitis- an animal model of MS- CBD reduces the migration of T cell lymphocytes to the site of inflammation.
But, if you’re a healthy person, you may be thinking that these are things you don’t want. The immune system helps us to survive, so why would we want to suppress it?
It all comes back to homeostasis. The ECS strives to maintain a balance in your body, and CBD will support it in achieving this. Because of this, CBD will likely cater to your body’s needs. If your immune system is overactive, it could counterbalance it; if it needs a boost, CBD may give it just that.
CBD and immune system support
Although this avenue is less researched, there is some evidence to suggest that CBD is immunomodulatory and can promote immune function.
In various animal studies, CBD has been shown to increase the production of pro-inflammatory cytokines and enhance the breakdown of pathogens. Much of this experimental evidence is from healthy animals or cell cultures which suggests that, under normal conditions, CBD helps to balance and boost the immune system.
Interestingly, CBD’s immunosuppressive effects have no impact on natural killer (NK) cells. These are the primary lymphocytes involved in combatting infections and tumour cells. This implies that, by protecting the activity of NK cells, CBD plays a role in maintaining immune health.
So, CBD can either suppress or boost the immune system. Understandably, this is a little confusing for the consumer- but allow us to explain. The effectiveness of CBD is said to be biphasic. This means that, depending on the dosage administered and how active our immune system is, CBD can act in opposing ways. The frustrating thing, however, is that the optimal dosage for immune support is not yet known.
Perhaps the most feasible way in which CBD could boost our immune system is by improving other aspects of our mental and physical wellbeing. Our lifestyle is a major predictor of our immune health; mood, sleep, and diet are all things that, when out of balance, can weaken our immune system. There is solid evidence to suggest that CBD can promote a healthy lifestyle, thus indirectly providing immune support.
The impact of psychological stress on our physical health is often overlooked. Chronic stress can dysregulate our immune response, triggering a constant low-grade inflammation that makes us more susceptible to disease and can worsen symptoms of illness.
CBD has been well researched in the context of anxiety. By increasing the signalling of serotonin– the ‘happy hormone’- in the brain, it shows promise in the treatment of numerous anxiety disorders. As CBD appears to be hugely effective at managing anxiety, this can help to limit the impact of stress on the immune system.
The body operates like clockwork. Like many of our biological systems, the immune system follows a rhythmic daily cycle, called a circadian rhythm. To function optimally, our immune cells sync to our sleep-wake cycle. So, if our sleeping pattern is thrown off, we’re far more likely to get ill.
Just like stress, sleep deprivation can cause a low-level inflammatory response. This compromises our immunity, making us more vulnerable to infections and disease. So much so, that extreme shift work has been linked to higher incidences of diabetes, heart disease, and arthritis.
CBD is used by many as a natural sleep aid. There is preliminary evidence to suggest that CBD may be an effective treatment for insomnia, though more research is needed. But the anecdotal evidence is there; in a survey of 387 CBD users, 42.5% of participants reported that they used CBD to overcome sleeping problems. So, it’s likely that a daily dose of CBD can help us to get our 8 hours in, therefore boosting our immune system.
Much of the immune system is located in our gastrointestinal (GI) tract. The ECS facilitates communication between the digestive system and immune system, helping to withstand inflammation in the gut. So, when the GI tract becomes inflamed, this can have a negative impact on our immune function.
The ECS helps to maintain immune health in the gut through the endogenous cannabinoid, anandamide. Also termed the ‘bliss molecule’, anandamide can work wonders for our mood. But it has also been shown to support immune function. In one animal study, oral administration of anandamide increased the number of immune cells in the gut and was protective against type 1 diabetes.
But how does this link to CBD? By inhibiting the FAAH enzyme, CBD prevents the breakdown of anandamide, subsequently increasing its levels in the body. Although this hasn’t yet been tested in the context of gut health, CBD may be able to indirectly improve immune function in the gut.
CBD also directly reduces inflammation in the GI tract. Not only does this make CBD a promising treatment for inflammatory bowel disease, but this may also help to maintain our gut health and keep our immune system functioning efficiently.
How to take CBD to support your immune system
There are countless ways to get your dose of CBD, but our understanding is limited in terms of which method of administration is best for immune support.
For those using CBD for immediate pain relief or to manage anxiety, most prefer to take a high dose of a CBD oil or vape, as these have the quickest onset. Though, for immune support, it is likely that a daily dose would be more beneficial than an as-and-when approach. This is because CBD builds up in your system over time, so its cumulative effects may help to build your immune system.
For a consistent daily dose, CBD capsules and gummies are a good option. The only issue here is its bioavailability. CBD is lipid-soluble; it doesn’t dissolve in the stomach very easily. Therefore, a good chunk of our CBD is broken down in the digestive system before it is absorbed. In order to get the most out of your oral dose, be sure to take it with food rich in fat as this has been shown to increase its bioavailability 3-fold.
Things to know before trying CBD
CBD is becoming a hugely popular supplement, with people all over the world raving about its therapeutic benefits. But be sure to consult your doctor before adding CBD to your routine, as it has been shown to interact with certain medications.
CBD has been deemed a safe and well-tolerated substance. There have been reports of tiredness, nausea, and appetite changes with CBD use, but these side effects are rare and mild in comparison to common over-the-counter meds.
A tremendous amount of research still needs to be done. There is evidence in favour of using CBD to boost and suppress the immune system, and even experts in the field can’t say for certain how CBD will influence immune activity from person to person. So, be wary of bold health claims being made about CBD in an attempt to piggyback off the growing trend. The science is promising, but it isn’t yet there.
That being said, there are undeniable benefits of CBD use that will more than likely support the immune system. Every single one of us will have given the concept of immunity some thought over the last year or so. So, for those keen to take measures to boost their immune system in over the winter, it might be worth giving CBD a try.