Endocannabinoid Tone and Sleep

Sleep is an essential action activated by the nervous system.

It's stimulated by neurotransmitters that control which parts of the brain remain active as we sleep.

During sleep, the body can replenish energy levels and boost brain function.

It also supports the formation of new neural pathways that build new memories and hold information. 

A good night's sleep should be between 6 to 9 hours and involves a cycle of sleep phases; 1, 2, 3, 4 and rapid eye movement (REM).

As you drop deeper into sleep, the phases progress from 1 to REM and then starts over again until you wake up.

Not getting enough sleep or only achieving light, poor quality sleep significantly increases the risk of a range of health problems and conditions:

• High blood pressure
• Heart disease
• Diabetes, 
• Infertility
• Loss of sex drive
• Depression
• Obesity

In the UK, 36% of adults regularly struggle to sleep, and 20% have difficulty sleeping every night.

The cause of this varies, but there are a few relatively common sleep disorders:

• Insomnia
• REM Sleep Behaviour Disorder
• Hypersomnia

What is CBD?

CBD is a beneficial cannabinoid that is commonly consumed in oils, capsules, e-liquids or gummies as a natural health supplement.

When it enters your cells and tissues, it interacts with a broad range of chemical messenger molecules, enzymes and receptors.

These interactions support your body's ability to restore your body systems to a state of healthy balance.

Learn more about CBD with our guide: CBD 101 – Everything you need to know

CBD and Your Endocannabinoid Tone

Endocannabinoid tone is the level of potential endocannabinoid activity in your body and the ability of your endocannabinoid system (ECS) to respond to any problems.

When you take CBD, it interacts with the enzymes of your ECS in a way that raises your endocannabinoid tone.

If your endocannabinoid tone is low, your ECS is unlikely to be able to restore your body systems to a state of healthy balance. As a result, you may feel unwell or experience symptoms related to anxiety. 

To learn more about your endocannabinoid tone, you can read our article: Endocannabinoid Tone and CBD.

Endocannabinoid Tone Key terms:

CB1 and CB2 – These are the most common endocannabinoid receptors.

• CB1 is found in the central nervous system.
• CB2 is present in the central nervous system, the peripheral nervous systems and in immune cells throughout the body

Anandamide (AEA) and 2-Arachidonoylglycerol (2-AG) – These are endocannabinoid signalling molecules present in humans and animals.

They can interact with a range of chemical receptors including CB1 and CB2.

FAAH and MAGL - These are the enzymes responsible for breaking down cannabinoids in our body once they have completed their message signalling.

Insomnia and your Endocannabinoid Tone

Insomnia refers to difficulty falling asleep or staying asleep. If it lasts for more than three months, it's known as long-term insomnia. 

For most people, insomnia includes:

• Struggling to go to sleep
• Wake up several times throughout the night
• Waking up early and not being able to get back to sleep
• Feeling tired and irritable during the day

Some of the most common causes are:

• Stress, anxiety or depression
• Irregular sleep times 
• Illness 
• Pain, 
• Side effects from medication
• Sleep disorder

Studies on the role of endocannabinoids in sleep have discovered that the level of the endocannabinoids anandamide and 2-AG fluctuate throughout the sleep cycle.

Also, CB1 endocannabinoid receptors are abundant throughout areas of the brain that are essential to sleep. 

As a result, scientists believe that endocannabinoids produce a range of different actions that assist the control of the sleep cycle and help the brain to move from one phase to the next.

When anandamide and 2-AG bind with CB1 receptors, they modulate the release of neurotransmitters that alter synapse activity. 

A scientific review conducted in 2020 concluded that this action indicates that a raised and balanced endocannabinoid tone could promote a healthy sleep cycle and may reduce insomnia.  

REM Sleep Behaviour Disorder and your Endocannabinoid Tone

Rapid eye movement (REM) sleep behaviour disorder is a condition when a person physically acts out dreams while they're still asleep.

This can include talking, shouting or lashing out with arms and legs.

REM sleep is the phase when dreams occur, but in most people, there are neural pathways in the brain that are activated to prevent any dream activities resulting in physical movement.

However, in the brains of people who have REM sleep behaviour disorder, these pathways don't start correctly. 

This condition affects approximately 1% to 2% of adults and it can develop gradually over time.

It's not yet completely understood what causes REM sleep behaviour disorder, but several risk factors have been identified:

• It's more common in men
• It can start at any age but is most common over 50.
• It's commonly linked to other conditions, including narcolepsy, brain tumours, Parkinson's disease, stroke and dementia.
• It may be linked to some medications 

So far, there are very few clear links between the endocannabinoid system and REM sleep behaviour disorder.

While a medium or high endocannabinoid tone is likely to support the correct regulation of sleep, most studies didn't find a link between increased ECS activity and a reduction in REM sleep behaviour disorder.

However, one study discovered that patients with REM sleep behaviour disorder linked to Parkinson's disease showed a significant improvement in sleep activity symptoms when their ECS was stimulated.

The scientists involved in the research proposed that this specific form of REM sleep behaviour disorder may be caused by the depletion of a certain type of brain cell called mesencephalic cholinergic neurons.

When the endocannabinoid tone is balanced or naturally high, CB1 activation in the areas of the brain related to sleep (basal prosencephalon and the pedunculopontine and laterodorsal nuclei16) stimulates the expression of these mesencephalic cholinergic neurons.

This promotes the release of the neurotransmitter acetylcholine17 which is involved in preventing body movement during sleep.

Hypersomnia and your Endocannabinoid Tone

Hypersomnia, or excessive daytime sleepiness, is a condition that causes a person to fall asleep several times during the day.

In most cases, it's not related to a lack of sleep at night or overtiredness but is caused by an underlying condition such as narcolepsy, sleep apnea or injury to the head or central nervous system.

Why hypersomnia occurs and what is happening in the brain when it does is not yet fully understood.

When studies involving brain scans of patients with hypersomnia were conducted, no concrete conclusions were drawn.

However, some scientists have still been able to create a working suggestion for how it might interact with the endocannabinoid system.

Studies with hypersomnia patients observed that an increase in endocannabinoid tone increased wakefulness during the day and reduced hypersomnia symptoms. They were able to link this effect to dopamine and serotonin levels in the brain.

Activation of the endocannabinoid system stimulates the production of dopamine and serotonin.

When these two neurotransmitters are in balance, they influence melatonin levels to modulate the proper function of the sleep-wake cycle and reduce the instances of excessive daytime sleepiness.