When it comes to sleep, several plants have been backed up with research and anecdotal evidence to being helpful natural sleep aid remedies.
Three popular herbs for sleep are valerian, lavender, and chamomile. Here we help break down the research, and how these herbs compare against each other.
Herbs for sleep
Why is it that these herbs work for sleep?
The main reason is because they’re positive modulators for gamma-aminobutyric acid (GABA).
What is gamma-aminobutyric acid (GABA)?
Gamma-aminobutyric acid (GABA) is one of our body’s main sedative neurotransmitters. GABAergic neurons are located in the hippocampus, thalamus, basal ganglia, hypothalamus, and brainstem. They have receptors that slow your brain by blocking signals to your central nervous system.
A modulator of GABA binds to this receptor to induce sedative effects. This depresses brain activity, reducing its ability to receive and make chemical messages. This sedative effect is what contributes to relieving stress, reducing anxiety (of having anxiolytic effects), and even improving sleep.
These modulators, called positive allosteric modulators (PAM) increase the effect of GABA by making the channel open more frequently or for longer periods. They trigger the GABAA receptor to open its chloride channel to allow chloride ions into the neuron. This makes the cell hyperpolarized and less active. So this is how relaxing, sleep-inducing effects are triggered.
Pharmaceutical modulators include sedatives like benzodiazepines, barbiturates, and anesthetics, all known medical sedatives.
Lavender, chamomile, and valerian all either contain components or are themselves positive allosteric modulators of GABA.
Lavender is a plant that’s used commonly in aromatherapy. Its relaxing, anxiolytic properties come from linalool, which is a positive allosteric modulator (PAM) of GABAA.
Linalool and GABA
The essential oil of lavender has been shown to have affinity for GABAA receptors.
Linalool is a monoterpene compound, found in essential oils of many aromatic and citrus species. Studies have found they have marked sedative effects on the central nervous system.
For sleep and stress
Lavender has been shown to be very helpful for sleep and stress and general anxiolytic (reducing anxiety) properties. A study found that people taking 80mg of lavender for 6 weeks experienced reduced depressed moods, sleep disorders, restlessness and anxiety as well as improved cognitive functioning.
Lavender aromatherapy was found to reduce anxiety in the setting of trauma and a better mood.
Another study found that lavender supplements helped reduce anxiety in generalized anxiety disorder without side-effects from sedation.
When it comes to sleep, lavender aromatherapy was able to relatively improve sleep quality in women with insomnia, also associated with a reduced heart rate. These results were replicated in college students who reported difficulty sleeping from stress, and then again in a small group with general insomnia.
You can take lavender as an oral supplement, which typically contains lavender oil. The recommended daily amount of lavender is 80 – 160 mg, which is made of around 25 – 46% linalool.
Many people use lavender essential oils for aromatherapy.
Topical lavender oil is also available, but there’s a possibility of skin agitation and damage. So this cannot be recommended to everyone.
The pros: Lots of studies have found beneficial effects of lavender in reducing stress, anxiety, and restlessness, all of which contribute to getting better sleep across diverse populations and sleep conditions, including in insomnia. Numerous studies have cited the benefits of lavender and have recommended it as a therapeutic treatment.
The cons: There are a few minor side-effects with using or taking lavender. Orally consuming it could also result in constipation, nausea, or headaches. Topical lavender is another form factor, but comes with a risk of causing skin irritation.
Lavender is incredibly useful as a sleep aid and has proven sedative effects that contribute to improved sleep quality and reduced anxiety. While some topical forms aren’t recommended, oral supplementation can be used to possibly support improved sleep quality, even in cases of difficulty sleeping.
Ultimately it’s a well-supported sleep aid, with some precautionary elements as to taking it.
Next is valerian, a root that’s typically brewed as a tea or consumed. Valerian is primarily used for relaxation, to soothe anxiety, and to make it easier to go to sleep.
Valerian and GABA
Valerian contains flavonoids that are also positive modulators of GABAA receptors, such as valerenic acid which binds to the β3 subunit of the GABAA receptor, either directly activating GABAergic signaling or enhancing the activity of other agents that increase GABAergic signaling.
Studies found valerian extracts appeared to enhance the signaling of GABA at “higher-than-expected concentrations,” especially so when supplemented orally.
For sleep and anxiety
Valerian has traditionally been used to treat anxiety, having anxiolytic properties.
How does it work for sleep? In early studies, valerian showed significant improvement in total sleep time, sleep latency, and reduced number of nightly awakenings in groups with insomnia.
Later studies, however, reported that they found no difference in sleep quality nor evidence to support an improvement in sleep quality in either healthy persons or those with insomnia, as assessed using objective sleep measurements.
However, valerian is known to cause mild sedation, which may contribute to feeling improved sleeping quality or easier time sleeping.
The RDA for valerian is around 450mg.
High doses were associated with feeling drowsiness the next morning, so those who may be sensitive to its effects should be cautious about taking too much.
The pros: Taking high doses of valerian has sedative effects, and the initial pilot tests with valerian showed significant improvement in total sleep time,sleep latency, and reduced number of nightly awakenings in groups with insomnia. Actually, its ability to enhance GABA has higher-than-expected concentrations during oral supplementation.
The cons: Studies about valerian and improving sleep are inconsistent. While initial pilot studies found favorable results in improving sleep with valerian, future trials found statistically insignificant effects. One study found no difference in sleep quality between people taking valerian vs. taking a placebo.
Chamomile is another plant that contains a bioflavonoid, apigenin, that produces sedative effects.
Apigenin and GABA
Apigenin enhances the GABAergic system and possesses anxiolytic effects by acting as a benzodiazepine ligand and has sedative effects at high doses.
Chamomile is approximately 0.8-1.2% apigenin by weight.
For sleep and daytime functioning
Chamomile extract was examined for its preliminary efficacy and safety for improving sleep with chronic insomnia. In this study, oral intake of chamomile was found to make a positive difference in average sleep quality.
However, in trials related to insomnia, they found no significant differences between groups in changes in sleep diary measures, which included total sleep time, sleep efficiency, sleep latency, wake after sleep onset, and sleep quality.
But from this same study, they concluded that chamomile treatment could provide modest benefits in terms of daytime functioning, which might influence mixed benefits for sleep.
There is no official RDA from chamomile. People make chamomile tea, which is caffeine-free and easy to take prior to one’s desired bedtime.
The pros: In studies conducted on non-insomnia populations, there’s evidence of some improvement in sleep quality over a period of time. One study actually found that chamomile flower extract moderately improved daytime functioning after taking it the night before.
Cons: In studies that did involve insomnia, there was no significant improvement in sleep using chamomile. Similarly, nothing conclusive was found on chamomile’s impact on anxiety.
So while chamomile has an undetermined impact on anxiety and insomnia, it may help improve sleep quality for other groups of people, as well as improving daytime functioning.