Beyond melatonin, natural amino acids can help us relax and improve sleep
When it comes to natural sleep aids and relaxation support, we tend of think of melatonin. As helpful as this supplement can be, it can cause morning grogginess in some people. Thankfully, there are many other nutraceuticals well shown to support relaxation and healthy sleep:
Gamma aminobutyric acid (GABA)
The balance of the neurotransmitters glutamate and gamma-aminobutyric acid (GABA) in the central nervous system plays an important role in the brain’s excitability. An appropriate balance of excitation and inhibition is necessary for healthy sleep, a balanced mood, memory, and other cognitive processes. Glutamate is the main excitatory neurotransmitter while GABA is the main inhibitory neurotransmitter. Lower GABA concentrations have been shown to be associated with poor sleep quality and have been demonstrated in individuals with major depressive disorder and anxiety.,, GABA also helps to reduce the response to fear or anxiety-provoking stimuli. Many sedatives bind or stimulate GABA receptors, reinforcing the importance of this neurotransmitter for sleep.
In people with attention deficit hyperactivity disorder (ADHD), significantly lower GABA levels have been observed in a region of the brain known as the anterior cingulate cortex, an area associated with decision making, emotion, and impulse control.
In people with attention deficit hyperactivity disorder (ADHD), significantly lower GABA levels have been observed in a region of the brain known as the anterior cingulate cortex, an area associated with decision making, emotion, and impulse control. Additionally, the lower the GABA levels, the more common the impulsivity behaviors were. Glutamate, on the other hand, has been shown to be twice as high in children with ADHD, tipping the balance to that of an excitatory state. Supplemental administration of GABA has been shown to significantly increase alpha wave patterns in humans, accompanied by reduced levels of anxiety., Alpha waves predominantly occur during wakeful relaxation, and are present during activities such as meditation. Orally, GABA is usually well tolerated but some may experience side effects such as nausea, tiredness, and a mild decrease in blood pressure at higher dosages.,
Although the ability of supplemental GABA to cross the blood-brain barrier (BBB) under normal conditions is questionable, there is evidence of a specialized GABA transporter in the BBB. There also are many settings in which the permeability of the BBB is increased, including with exposure to inflammatory agents such as histamine and bradykinin. It also has been proposed that the effects seen clinically with GABA are due to the binding of receptors in the nervous system within the digestive tract, and are modulated by the vagus nerve. Additionally, liposomal delivery systems may facilitate transport across the BBB and increase availability of therapeutic agents in the central nervous system.
Green tea is well known for its high amounts of antioxidants, particularly one known as epigallocatechin gallate or EGCG. However, green tea also contains a high amount of an amino acid known as L-theanine.
Studies have shown that L-theanine increases alpha-wave activity in the brain, as well as the levels of the neurotransmitters serotonin, dopamine and GABA., L-theanine has been shown to protect the nervous system,, and to increase the levels of the antioxidant glutathione as well as its recycling enzymes under stressful settings. It has also been shown to support the growth of new nerves and new pathways in the brain.
L-theanine continues to be studied for the impacts it may have on learning and memory, attention, mood, and even other mental health conditions such as schizophrenia, and has been shown to be well tolerated.
Clinically, supplementation with L-theanine has been shown to have a relaxing effect, reducing anxiety as well as heart rate and blood pressure in acute stressful events and during mentally challenging tasks.,, L-theanine has been shown to reduce subjective experiences of stress and salivary α-amylase activity, a marker of sympathetic nervous system activity and the “fight or flight” response, during academic challenges. At a dosage of 200 mg daily, L-theanine has been shown to significantly reduce emotional symptoms of premenstrual syndrome, including irritability, anger, mood swings, and crying. In children with ADHD, L-theanine has also been shown to improve sleep quality and has been studied and found safe to be used for this purpose at doses of 200 mg twice daily. L-theanine continues to be studied for the impacts it may have on learning and memory, attention, mood, and even other mental health conditions such as schizophrenia, and has been shown to be well tolerated.
5-hydroxytryptophan (5-HTP) is an amino acid produced in the body from the essential amino acid tryptophan. 5-HTP is the immediate precursor to serotonin, which converts to melatonin. The enzyme 5-hydroxytryptophan decarboxylase converts 5-HTP to serotonin and requires vitamin B6 (pyridoxine)., 5-HTP is well absorbed orally, and easily crosses the blood brain barrier.
In children, at a dosage of 2 mg/kg at bedtime, 5-HTP has been shown to significantly reduce the occurrence of night terrors, with no negative side effects.
In children, at a dosage of 2 mg/kg at bedtime, 5-HTP has been shown to significantly reduce the occurrence of night terrors, with no negative side effects. In another study done in children, 5-HTP was found to improve sleep, particularly by reducing the number of night-time awakenings. In adults with normal healthy sleep, 5-HTP was observed to increase rapid eye movement (REM) portion of sleep, implying more restorative rest.
5-HTP has been studied in different settings of acute anxiety and shown to significantly reduce the reaction to panic challenge in patients with panic disorders. In patients diagnosed with anxiety disorders, supplementation with 5-HTP led to a moderate reduction of symptoms as measured by various common tools used to assess anxiety. The combination of GABA and L-theanine has also been studied and shown to significantly improve sleep quality as compared to administration of either individually., Long-term administration also was observed to increase levels of GABA and its receptor.
Side effects that can occur with higher dosages of 5-HTP can include nausea, vomiting, and diarrhea. 5-HTP conversion to serotonin peripherally has the potential to increase gut motility. Because of its effects on serotonin production, it is probably safest to avoid combining 5-HTP-containing supplements with tricyclic antidepressants, monoaminoxidase inhibitors, selective serotonin reuptake inhibitors (SSRIs), until more large-scale studies demonstrate the safety of combining 5-HTP with these medications.
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