If you’ve been paying attention to the natural health world the past few years, you will surely have noticed that therapeutic/medicinal uses of cannabis are being discussed more-and-more every month.
And for good reason. Thanks to a dramatic increase in research in the past 5 years, the body of data we now have on therapeutic uses of cannabis is as staggering in size as it is promising.
While the cannabinoid THC has historically received the bulk of the attention due to its well-known psychoactive properties, it is actually the non-psychoactive “secondary” cannabinoid, cannabidiol (CBD) that is of the greatest interest to many researchers, myself included.
Before we dive into why CBD is so intriguing as a therapeutic or performance-enhancing tool, let’s take a step back and look at the function of cannabinoids in the body.
(the next couple sections will be quite useful if you want to understand how CBD works in the body, but they also get a bit technical, so feel free to skip ahead)
First, The Endocannabinoid System
Endocannabinoid is short for “endogenous cannabinoid” - which essentially means it is a system of signaling molecules and receptors produced by and native to our own bodies.
The endocannabinoid system is one of the more recent systems to be discovered within our own bodies, with the first receptors being discovered only in the late 80’s.
A couple of decades later, we’re still very much in the infancy of understanding this system and its role in the body. Researchers have identified the importance of the endocannabinoid system in immune function, pain management and appetite control among other things, but the exact mechanism of these actions is still being parsed out. 
My own sense of this after analyzing who-knows-how-many dozens of studies on CBD, is that the overall function of the endocannabinoid system is to maintain balance in the nervous system. Here's why:
In the nervous system, almost all signaling molecules move with the direction of the synaptic firing - that is from the neuron sending the signal to the one receiving it.
Endocannabinoids, on the other hand, are relatively unique in being “retrograde transmitters” - meaning they travel in the opposite direction of synaptic flow (from signal-receiving-neuron to signal-sending-neuron).
The presence of endocannabinoids in a synapse temporarily reduces the amount of neurotransmitter released from the sending neuron. Functionally, this means the receiving neuron is able to exert some control over the amount of neurotransmitter it receives.
This neuron-level feedback mechanism is likely at the core of the balancing effect endocannabinoids have on our nervous system.
How Does CBD Affect Our Endocannabinoid System?
The interaction of CBD with our body’s endocannabinoid system is complex.
Unlike THC, CBD has a low affinity for our endocannabinoid receptors, so its activity does not come from direct action on these receptors.
Instead, CBD increases the activity of our own endocannabinoid signaling molecules in the nervous system. CBD does this by 1) increasing cannabinoid receptor density and 2) by inhibiting a key enzyme that breaks down our endocannabinoid signaling molecules (particularly anandamide).
What I find most intriguing, however, is that CBD also interacts with the serotonin receptor 5-HT(1A), which appears to produce the anxiety-relieving, antidepressant and neuroprotective effects we’ll touch upon later.
CBD For Inflammation, Pain and Arthritis
Some of the best researched applications for CBD are in the management of pain and inflammation.
Reduces Inflammation - CBD has been shown to inhibit several of the enzymes that trigger an inflammatory response in the body. That being said, the anti-inflammatory effect is nowhere near as powerful as what a high-quality turmeric extract is capable of producing.
However, because CBD predominantly inhibits different pro-inflammatory enzymes than turmeric (iNOS vs COX-2), the turmeric and CBD complement each other wonderfully and produce a very significant anti-inflammatory effect when used in tandem.
- Combats Arthritis - Arthritis is the net effect of several biochemical processes that occur in and around the connective tissue, and CBD has been shown to slow a remarkable number of these. Beyond reducing inflammation in the joint, CBD also inhibits damaging “reactive oxygen species” in the joint - a prime factor in the arthritic degradation of connective tissue. 
CBD For Intestinal And Cardiovascular Health
- Intestinal Health - Lining our small and large intestines is a single-cell thick layer called the epithelium, which is responsible for transporting nutrients from the gut into the bloodstream. The epithelium is also the barrier that keeps undigested food and bacteria in our gut from entering the blood. When this barrier is disrupted, food particles and bacteria are able to pass into the bloodstream, triggering an intense inflammatory response in the gut, and over time, throughout the body.
CBD has been shown to reduce inflammation in the gut and preserve epithelial barrier function in patients with high glucose (which generally causes epithelial dysfunction).
- Cardiovascular Health - CBD has been shown to reduce myocardial dysfunction, cardiac fibrosis, oxidative/nitrative stress, inflammation and cardiovascular cell death. 
CBD For Stress Resilience, Neuroprotection And Mental Performance
This is why I personally supplement with CBD and why I believe it to be beneficial for nearly everyone to include in their daily supplementation.
The brain benefits derive largely from CBD's action as a partial agonist of the 5-HT(1A) serotonin receptor:
Stress Resilience - This is the biggest effect I notice with CBD supplementation: resistance to stress is improved significantly. A low level of stress can actually improve mental performance for a lot of people (myself included), but cross that magic stress-threshold and it pretty quickly becomes a huge liability to mental performance and energy.
CBD effectively keeps me below this mental-performance-stress-threshold much longer than I would otherwise expect to in a given situation. I remain clearer and more balanced, and my mental performance and output improve as a result.
This effect has been demonstrated in a number of studies as well - CBD has been shown to attenuate autonomic stress responses (via 5-HT(1A) neurotransmission) in both rats and humans. 
- Antidepressant - Assumedly via this same 5-HT(1A) serotonin receptor activity, CBD has also shown significant antidepressant activity in mice. 
There is some speculation (which I agree with...) that the antidepressant and anxiolytic effects are also likely a result of CBD increasing levels of endocannabinoids in the body (like anadamide) by inhibiting their breakdown. 
- Neuroprotection - This is perhaps where CBD is most impressive. The variety of mechanisms through which CBD confers a neuroprotective effect is stunning.
The primary way in which brain and nerve cells are damaged is through oxidation. CBD reduces oxidative damage in the brain by functioning as an antioxidant. More meaningfully, however, it also stimulates production of brain-derived neurotrophic factor (BNDF). BNDF, in turn, initiates the repair of damaged neurons and the growth and differentiation of new neurons. 
One of our brain’s key mechanisms for protecting itself from toxins that circulate in the rest of the body is the blood-brain-barrier (BBB). So as to protect the brain and separate it from hormonal communication happening elsewhere in the body, a properly functioning BBB allows very few types of molecules through. When the body is chronically inflamed, it is common to see the BBB compromised, letting toxins reach the brain and causing neurological inflammation. CBD has been shown to prevent this inflammation-caused disruption of BBB function, thus reducing neurological inflammation. 
The list goes on…
CBD reduces scarring in nervous tissue after oxidative damage (via reducing expression of neurotrophin S100B). 
CBD confers a neuroprotective effect by stimulating cerebral blood flow (this would also produce cognition enhancement). 
And finally - remarkably - there does not seem to be a tolerance developed to CBD as you see with most other bioactive compounds. The neuroprotective effects produced by CBD do not to decrease over time. 
My CBD Supplement Recommendation
First, a word on the legal status of CBD. CBD oil, if derived from a psychoactive cannabis plant, would still be considered "scheduled" (i.e. not legal) in the US.
Thankfully in the past few years, a number of innovative manufacturers have started deriving very clean, high-quality CBD oil from organic industrial hemp. Because industrial hemp (and all of its derivatives, like CBD oil) are FDA approved and legal, these hemp-derived CBD products are legal for sale in all 50 states.
I've tried about a dozen hemp-derived CBD products over the past few years, and one stands out head-and-shoulders above the rest in potency, both for inflammation- and pain-reduction and for mental performance.
SOL CBD Liposomal Cannabidiol has been my daily CBD supplement of choice for the past few years. SOL's product is noticeably more potent/effective than the other CBD oils I've tried, likely attributable to the increase in absorption from the gut thanks to the liposomal formulation.
It's bit pricey, but I've found 7-9mg of CBD per day is ideal for me, and a bottle lasts me about a month and a half.
Wishing you peace + health,
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