What Research Says About CBD For Anxiety

Perhaps one of the most popular uses of CBD is for anxiety. Both anecdotally and clinically, CBD is quickly becoming the remedy of choice. Maybe your kids are driving you nuts, you have a particularly stressful stretch at work or your baseline anxiety is just on the rise in general. 

CBD is a promiscuous chemical in the body, it pushes a lot of different buttons all at the same time, which is how it's able to have a profound impact on anxiety. 

We talk about the Endocannabinoid System (ECS) a lot, and its pivotal role in maintaining homeostasis in the body. Well, one of its main tasks is to regulate stress and mood across the various neuronal and hormonal highways throughout the body. CBD works a lot of its magic by helping the ECS keep the peace across bodily systems, which in turn controls mood. 

CBD increases the levels of a key Endocannabinoid, called Anandamide. Anandamide literally translates to ‘bliss chemical’ in sanskrit, which as you can probably tell by the name, has a powerful effect on mood. 

Anxiety has been suggested to be related to an Endocannabinoid Deficiency. Endocannabinoids are essential for balancing hormonal and neuronal systems which keep us happy, calm and collected. So when they are out of whack, so are the systems which rely on them. 

We're going to have a look at just what gives CBD its anti-anxiety properties, a little about how it works and what results from a few CBD clinical trials demonstrate.

CBD and Anxiety: Mechanisms

GABA and Glutamate Neuronal Systems

Glutamate and GABA are two opposing brain chemicals which control the balance between excitation/arousal and inhibition/relaxation. Anxiety is associated with too much glutamate signalling (1), and a lack of GABA signalling similarly perpetuates anxiety. 

Image Source: Wierońska et al., 2011 

For anxiety to resolve, GABA signalling often needs a helping hand. Restoring GABA is how benzodiazepine drugs, and to a lesser extent herbal teas like chamomile and valerian work to induce relaxation. 

CBD acts on two levels to have a profound impact on GABA signalling. 

1. Via the ECS; It boosts levels of Anandamide; which is one of the gatekeepers for balancing levels of GABA:Glutamate and thus the balance between arousal and relaxation
2. Independently of the ECS; it modifies one particular type of GABA receptor to ‘turn up the volume’ of GABA signalling. 

These two mechanisms are how CBD exerts much of its anti-anxiety power, re-balancing brain chemistry and calming mental turbulence.

Serotonin Signalling

Another way CBD helps to alleviate anxiety is by supporting serotonin signalling in various parts of the brain. Serotonin is needed to foster feelings of safety, security and stability. Some people may lack the ability to produce sufficient serotonin, either from a genetic standpoint or through their circumstances in life. 

Conventional (pharmacological) approaches to managing anxiety involve the use of selective serotonin reuptake inhibitors (SSRI’s) to boost levels of available serotonin. Unfortunately, there are often side effects associated with manipulating serotonin signalling in this way. Increasing levels of serotonin globally can mean it can bind to many varieties of serotonin receptor, and thus elicit other effects other than mood regulation. 

CBD acts in a different, more targeted fashion. Instead of increasing serotonin globally, it activates a specific serotonin receptor called 5HT1A  (2). This translates to an increase in mood and reductions in anxiety, without the side effects. What CBD essentially does is trick the brain into thinking it has more serotonin than it does, without actually increasing it. In this way CBD mimics serotonins activity, without messing with all the other serotonin receptors. 

The ability for CBD to discriminate between certain serotonin pathways means that it has far less (if any) side effects when compared to SSRI's.

Adenosine Signalling

If you’ve ever drunk too much coffee, then you’ll know about anxiety. In the brain, you’ll find receptors which recognise caffeine, called Adenosine receptors. Under normal circumstances, Adenosine receptors keep a grip on how stimulated and excited our minds are. When we drink caffeine however, that blocks Adenosine receptors to increase stimulation, sometimes too much so and we become anxious. 

CBD activates a particular Adenosine receptor and also increases the concentration of Adenosine itself (3). Consequently, this reduces excessive stimulatory activity whether induced by caffeine or not, such as high heart rate, anxiety and blood pressure. 

This is why CBD has become a popular additive to coffee, for its ability to reduce the negative aspects of caffeine whilst keeping part of the buzz. 

Cerebral Blood Flow 

CBD also has been shown to alter blood flow to certain areas of the brain which are involved in mood regulation and emotional processing (4). Stress and anxiety modify the flow of blood to certain areas of the brain, so it may be that CBD can alter this flow in a way that alleviates the impact of anxiety. 

Clinical Studies with CBD on Anxiety

Robust studies with CBD are still to come, but a few preclinical studies paint an encouraging picture for anxiety. 

Most studies are short term (1-2 days), and have found that CBD has been acutely effective for anxiety in both healthy volunteers and those with anxiety. 

CBD was found to significantly reduce anxiety compared to placebo in healthy volunteers undergoing a public speaking test designed to elicit anxiety (5), (6). 

Under similar test conditions, CBD significantly reduced scores of anxiety, discomfort and cognitive impairment during the test compared to placebo in subjects with social anxiety disorder (SAD) (7). 

Purified CBD was used in these studies, at doses ranging from 300 - 600mg. 

Longer term use of CBD has been documented in a retrospective case series of 72 adults using CBD. After 1 month of CBD use, subjective scores of anxiety improved in 79% of patients, and remained decreased after 3 months (8). CBD was given in capsule form at 25mg/day, which was most likely whole-plant CBD.