Calm & Relaxation

Calm & Relaxation: A Nutritional and Natural-Health Reference

1. Definition and Scope

In the nutritional and natural-health context, "calm and relaxation" refers to the psychophysiological state in which the body's stress-response systems are appropriately regulated, allowing a subjective sense of ease, reduced tension, and mental tranquility. It is best understood not as the mere absence of activity, but as the presence of precisely controlled inhibitory and modulatory processes across several interacting body systems. The concept encompasses the counterpart to the acute and chronic stress response: a state in which the autonomic nervous system (ANS), the neuroendocrine axis, and key neurotransmitter networks are operating within balanced, homeostatic ranges.

Stress describes bodily reactions to perceived physical or psychological threats that trigger a cascade of physiological responses. Emotional responses to stress include anxiety, restlessness, and nervousness. The promotion of calm and relaxation, therefore, involves dampening or counterbalancing those responses through dietary, supplemental, herbal, and lifestyle approaches.

2. Body Systems Involved

2.1 The Autonomic Nervous System (ANS)

Physiological responses to stress are governed by two interrelated systems: the hypothalamic-pituitary-adrenal (HPA) axis and the autonomic nervous system (ANS). The ANS affects different bodily functions depending on a person's emotional state — for example, it increases heart rate in the event of a fight-or-flight response and reduces heart rate to bring the body back to a rest state.

The parasympathetic branch of the autonomic nervous system acts as a counterbalance to rapid stress responses, and maintains homeostasis by the secretion of neural transmitters such as acetylcholine, which leads to a decrease in heart rate and cardiac output. It is this parasympathetic predominance that characterizes the state of physiological relaxation.

2.2 The Hypothalamic-Pituitary-Adrenal (HPA) Axis

The hypothalamic-pituitary-adrenal (HPA) axis is a communication system between three organs that is crucial for managing the body's response to stress. More specifically, the HPA axis is a neuroendocrine system — it consists of cells that release hormones into the blood (via the endocrine system) in response to nervous system stimulation.

The HPA axis produces a chain reaction of hormones that eventually triggers the release of cortisol. In response to a stressful situation, the autonomic nervous system triggers the hypothalamus to release corticotropin-releasing hormone (CRH). CRH triggers the anterior pituitary to release adrenocorticotropic hormone (ACTH). ACTH then triggers the adrenal glands, specifically the adrenal cortex, to release cortisol.

The HPA axis is meant to have a fine-tuned negative feedback loop: the cortisol in the body then triggers the hypothalamus to stop making CRH, ending the stress response. Relaxation, in physiological terms, is substantially the restoration of this feedback loop to its resting equilibrium.

Cortisol is a key regulator of the stress response and has widespread effects on the body, with its major roles including the promotion of glucose formation via gluconeogenesis and the redistribution of energy to critical organs such as the heart and brain, while suppressing unnecessary functions such as the immune response and reproduction. Cortisol levels peak ten to thirty minutes following a stressful event and can remain elevated for approximately an hour after the event.

2.3 The GABAergic System

Gamma-aminobutyric acid (GABA) is a neurotransmitter — a chemical messenger in the brain. It slows down the brain by blocking specific signals in the central nervous system (the brain and spinal cord). GABA is known for producing a calming effect. It is thought to play a major role in controlling nerve cell hyperactivity associated with anxiety, stress, and fear.

There are several roles of GABA: a decrease in the activity of the neurons in the brain and central nervous system, relaxation, diminished stress, stabilization of the mood, decreasing of pain, and sleep improvement. GABA ensures that the brain does not transmit impulses "too quickly," helping to keep the average neuronal activity level in balance.

To have a properly functioning brain, a delicate balance must be maintained between the inhibitory effects of GABA and the excitatory effects of glutamate. An imbalance between GABA and glutamate is associated with neuronal hyperexcitability characteristic of pathological anxiogenesis.

2.4 The Serotonergic System

Serotonin is a neurotransmitter that plays a key role in mood regulation, emotional processing, and anxiety. Dysregulation of the serotonergic system is associated with anxiety disorders. L-theanine may have a role in regulating anxiety due to its effects on the serotonin and GABA systems.

2.5 The Sympatho-Adrenomedullary (SAM) Axis

In addition to direct innervation of target organs via the sympathetic nervous system, two main stress response pathways exist: the Sympathetic-Adreno-Medullary (SAM) axis and the Hypothalamus-Pituitary-Adrenal (HPA) axis. Activation of the SAM axis is a fast-acting physiological response and leads to an increased level of catecholamine hormones in the blood plasma and serum, including the "fight-or-flight" hormones adrenaline and noradrenaline.

2.6 The Gut-Brain Axis

Evidence indicates that gut microbiota modulate neurochemical pathways involving serotonin, dopamine, GABA, and glutamate, as well as immune and endocrine axes. Upon stress, the hypothalamus releases corticotropin-releasing factor (CRF) which disrupts the gastrointestinal system including oxidative damage to the colon, inflammation to the intestine, dysfunction of the intestinal barrier, and triggers immune response. This bidirectional relationship between gut health and psychological calm is an area of active research.

3. Contributing and Associated Factors

3.1 Chronic Stress and HPA Dysregulation

A stress response is mediated through a complex interplay of nervous, endocrine, and immune mechanisms, activating the sympathetic-adreno-medullar (SAM) axis, the hypothalamic-pituitary-adrenal (HPA) axis, and the immune system. When the stress response is maladaptive and detrimental to physiology, exposure to chronic stressors can cause maladaptive reactions, including depression, anxiety, cognitive impairment, and heart disease.

Within the Research Domain Criteria (RDoC) framework, dysregulated cortisol — whether excessively elevated or blunted — has been linked to disruptions in different processes of the negative valence, positive valence, cognitive, social, arousal, and sensorimotor systems. These effects are associated with distinct neural substrates, including limbic, striatal, and prefrontal control areas.

3.2 Magnesium Status

Magnesium (Mg) status is associated with subjective anxiety, leading to the proposition that Mg supplementation may attenuate anxiety symptoms. Low serum magnesium concentrations increase the release of stress-associated hormones including catecholamines, adrenocorticotrophic hormone and cortisol in response to stress, and affect their access to the brain, creating a vicious circle of reduced resistance to stress and further magnesium depletion.

3.3 Neurotransmitter Imbalance

When subjected to prolonged stress or anxiety, the brain depletes its available store of GABA and other inhibitory neurotransmitters. This can culminate in a full-blown anxiety or panic attack, accompanied by excessive sweating, trembling, muscle tension, weakness, disorientation, breathing difficulty, fear, and other symptoms.

3.4 Gut Microbiome Dysbiosis

There have been several reports where abundance of Lachnospiraceae, Romboutsia, and Faecalibacterium genera was reduced in patients with anxiety, depression, and autism, influencing neural, immune, and endocrine pathways. These effects may be mediated by low-grade inflammation and reduced tryptophan availability, which limit central serotonin synthesis and alter emotional regulation.

3.5 Sleep Deprivation

Anxiety may contribute to nightmares or insomnia, and sleep deprivation can also elevate the risk of an individual developing an anxiety disorder. The relationship between insufficient sleep and impaired capacity for calm is therefore bidirectional.

3.6 Omega-3 Fatty Acid Insufficiency

Low intake of omega-3 has a negative impact on sleep, causing tiredness and sleep disorders. Low intake of omega-3 has also been associated with low levels of attention and alertness, memory problems, irritability, and anxiety.

4. Nutrients, Herbs, and Natural Ingredients

4.1 Magnesium

Traditional Use

Magnesium has not historically been isolated as a distinct herbal or botanical remedy, but has been widely recognized through dietary traditions that emphasize mineral-rich plant foods — nuts, seeds, leafy greens, and whole grains — for sustaining vitality and mental equilibrium. Its formal isolation and study as a therapeutic agent belongs primarily to the modern nutritional sciences.

Scientific Evidence

Magnesium may modulate anxiety via increasing GABAergic availability by decreasing presynaptic glutamate release. GABA is a primary inhibitory transmitter in the CNS that counterbalances the excitatory action of glutamate. An imbalance between GABA and glutamate is associated with neuronal hyperexcitability characteristic of pathological anxiogenesis.

Eighteen studies were included in a systematic review published in Nutrients. All reviewed studies recruited samples based upon an existing vulnerability to anxiety: mildly anxious, premenstrual syndrome (PMS), postpartum status, and hypertension. Four of eight studies in anxious samples, four of seven studies in PMS samples, and one of two studies in hypertensive samples reported positive effects of Mg on subjective anxiety outcomes. Mg had no effect on postpartum anxiety. Existing evidence is suggestive of a beneficial effect of Mg on subjective anxiety in anxiety-vulnerable samples; however, the quality of the existing evidence is poor.

A more recent systematic review (PMC, 2024) confirmed that despite notable heterogeneity, the majority of included trials demonstrated at least modest positive results with regard to sleep quality and anxiety across diverse populations, consistent with animal-based evidence as well as magnesium's known receptor activity. Given the generally positive results across studies, the preponderance of preclinical evidence, and minimal side effects, supplemental magnesium is likely useful in the treatment of mild anxiety and insomnia, particularly in those with low magnesium status at baseline.

A randomized, single-blind clinical trial (PMC, 2019) found that animal and clinical studies suggest complementary effects of magnesium and high-dose pyridoxine (vitamin B6) on stress reduction. In stressed adults with low serum magnesium, healthy adults received either magnesium–vitamin B6 combination (300 mg and 30 mg/day, respectively) or magnesium alone (300 mg/day). This reported significantly lowered somatic anxiety symptoms on the HAM-A scale after 21 days (p < 0.004) and 42 days (p < 0.02) of treatment with Mg + vitamin B6 vs. placebo.

Evidence strength: Preliminary to moderate; evidence is suggestive but heterogeneous and methodologically variable across trials. Effect appears most consistent in individuals with existing deficiency or anxiety vulnerability.

4.2 L-Theanine

Traditional Use

L-theanine is a unique non-protein amino acid found abundantly in tea leaves. In East Asian traditions, particularly Japanese and Chinese tea culture, the practice of drinking Camellia sinensis tea — including green and matcha varieties — has long been associated with mental clarity, meditative calm, and a balanced alertness. Zen Buddhist monks are historically recorded as consuming green tea to promote a state of wakeful, non-agitated concentration during meditation, a state now understood to correlate with the alpha-wave activity that L-theanine produces.

Scientific Evidence

Several EEG studies have shown that L-theanine increases alpha activity, indicative of a state of wakeful relaxation. L-theanine increases attention-related anticipatory alpha activity while decreasing background alpha activity, potentially improving focus.

Research in lower mammals has reported a complex range of neurochemical actions associated with L-theanine administration, including inhibiting glutamate reuptake, increasing brain GABA and striatum dopamine and glycine concentrations, while serotonin levels were reported to decrease globally, with region-specific increases in the striatum, hippocampus and hypothalamus.

In a systematic review published in 2019 by Williams et al., L-theanine in its pure form at a daily dose of 200–400 mg reduced stress and anxiety in people under acute stress. One study explored changes in alpha activity within 60 minutes of administration of 50-mg and 200-mg doses of L-theanine in female participants (four high and four low in trait anxiety), reporting a dose-dependent increase in alpha power, significantly greater in the high-anxiety group. Higashiyama and colleagues also reported significantly elevated alpha activity during rest periods following 200-mg L-theanine administration, again only apparent in higher trait anxiety participants.

A 28-day randomized, double-blind, placebo-controlled trial found that 28-day supplementation with L-theanine was safe and well tolerated in a population of healthy adults with moderate stress, with all reported adverse events resolved by study end. L-theanine was safe and efficacious during an acute stress challenge. However, double-blind, placebo-controlled clinical trials investigating the longer-term effects of L-theanine supplementation on stress are warranted.

A 2025 PubMed review concluded that some studies suggest L-theanine may increase alpha waves in the brain associated with relaxation and selective attention, reduce stress and anxiety, and improve sleep quality, though findings are often inconsistent. Potential neuroprotective and anti-seizure effects have also been reported in animal models. The same review cautioned that the evidence supporting many health claims remains limited, especially given the lack of rigorous human clinical trials, and while L-theanine exhibits a good safety profile based on toxicology studies, caution is warranted regarding the purported health benefits until stronger scientific substantiation emerges.

Evidence strength: Preliminary to moderate. Alpha-wave induction in small EEG studies is replicated, but larger, adequately powered clinical trials for anxiety outcomes are still needed.

4.3 Ashwagandha (Withania somnifera)

Traditional Use

Ashwagandha is a key treatment herb in the Indian system of medicine that has been used for thousands of years. It has anti-inflammatory, neuroprotective, adaptogenic, and immunomodulatory activities. In Ayurvedic medicine, the dried root of Withania somnifera was prepared as a powder (churna) mixed with warm milk, clarified butter (ghee), or honey, and consumed as a rasayana (rejuvenating tonic) to build strength, promote sleep, and counteract the effects of overexertion and worry. It was categorized as a balya (strength-promoting) and medhya (intellect-enhancing) herb in classical texts such as the Charaka Samhita.

Scientific Evidence

Withania somnifera (ashwagandha) exhibits adaptogenic properties via withanolides that downregulate cortisol and improve sleep onset. It is hypothesised that some compounds in ashwagandha — mainly Withaferin A — can directly interact with glucocorticoid receptors in the brain, thus affecting cortisol and stress levels.

A 2024 systematic review and meta-analysis (PubMed, Explore) found nine randomized controlled trials involving 558 patients to be eligible, with the meta-analysis showing a significant effect of ashwagandha formulations on the Perceived Stress Scale (PSS) (MD = −4.72, 95% CI = −8.45 to −0.99). The findings indicate that ashwagandha formulations have beneficial effects on stress and anxiety, and the adverse effects associated with ashwagandha are limited; however, further information is required.

A 2025 meta-analysis published in BJPsych Open included a total of 15 studies with a combined sample size of 873 patients, finding that ashwagandha supplementation significantly reduced anxiety compared with placebo according to the Hamilton Anxiety Rating Scale (HAM-A). Doses ranged from 125–600 mg daily for 30–90 days; both root alone and root-and-leaf combined formulations were used.

A separate 2025 systematic review and meta-analysis (Albalawi, SAGE Journals) found a more nuanced picture: there was a statistically significant reduction in cortisol levels (−1.16 µg/dL, 95% CI: −1.64 to −0.69, p < 0.001), but no significant impact was observed on perceived stress (SMD = −0.355, 95% CI: −1.188 to 0.47; p = 0.40). This discrepancy between the biological marker (cortisol) and the self-reported measure (PSS) warrants further investigation.

Evidence strength: Moderate, with multiple well-designed RCTs. The cortisol-lowering effect is among the more consistently demonstrated outcomes for any botanical agent in this field. Long-term safety data remain incomplete.

4.4 Lavender (Lavandula angustifolia) — Silexan

Traditional Use

Lavender (Lavandula angustifolia Miller or Lavandula officinalis Chaix) has a long history of traditional use and its essential oil was found to possess a wide range of biological effects. Historically, lavender sachets, baths, and aromatic preparations have been used across European folk traditions to ease nervousness, promote sleep, and soothe headaches. In Mediterranean herbalism, dried lavender flowers were infused as tea or used in pillows to calm the mind before sleep. In German herbal medicine, lavender is listed in the Commission E monograph for nervous conditions.

Scientific Evidence

The most clinically studied form is Silexan, a standardized oral preparation derived from Lavandula angustifolia flowers by steam distillation. Silexan causes a potent inhibition of voltage-dependent calcium channels (VOCCs) in synaptosomes, primary hippocampal neurons, and stably overexpressing cell lines, which play an important role in both anxiety and depression. Inhibition of VOCCs can lead to an attenuation of the overreaching, situationally inadequate stress response of the CNS associated with anxiety and mood disorders. Moreover, Silexan significantly reduces the 5-HT1A binding potential in brain clusters encompassing the temporal gyrus, the fusiform gyrus, the hippocampus, the insula, and the anterior cingulate cortex, which may lead to an increase of extracellular serotonin levels.

A pivotal double-blind randomized trial (International Journal of Neuropsychopharmacology, 2014) enrolled 539 adults with generalized anxiety disorder (GAD) according to DSM-5 criteria, receiving 160 or 80 mg Silexan, 20 mg paroxetine, or placebo once daily for 10 weeks. The primary efficacy endpoint was the HAMA total score reduction. The HAMA total score decreased by 14.1 points for Silexan 160 mg/d, 12.8 points for Silexan 80 mg/d, 11.3 points for paroxetine, and 9.5 points for placebo. Both Silexan doses were superior to placebo (p < 0.01).

An earlier multicenter double-blind randomized study found that Silexan is as effective as lorazepam in adults with GAD, and the safety of Silexan was also demonstrated. Lavender oil showed no sedative effects in the study and has no potential for drug abuse.

Silexan taken orally at a daily dose of 80 mg for 10 weeks was significantly superior to placebo in reducing psychic and somatic symptoms of anxiety and was as effective as 0.5 mg/d lorazepam and 20 mg/d paroxetine. In patients with mild or moderate major depression, Silexan was superior to placebo and comparably effective to 50 mg/d sertraline.

A network meta-analysis (Scientific Reports, 2019) further confirmed that the effect of Silexan 80 mg was observed to be the same as that of paroxetine. Meta-analyses support its significant anxiety-relieving impact over placebo and comparable efficacy to lorazepam, but without sedation or withdrawal. Lavender aromatherapy is clinically the best route of administration for short duration, while Silexan (oral lavender) 80 mg is preferable for long-term treatment of anxiety.

Evidence strength: Among the strongest in the botanical category for anxiety. Multiple well-designed, adequately powered RCTs and meta-analyses support efficacy at 80 mg/day oral dose (Silexan). Silexan is approved as an over-the-counter medicine in Germany.

4.5 Valerian (Valeriana officinalis)

Traditional Use

Valerian is widely used as a traditional medicine to improve the quality of sleep due to interaction of several active components with the γ-aminobutyric acid (GABA) A receptor (GABA(A)R) system. In European herbal traditions, valerian root (Valeriana officinalis) has been used since at least the time of Hippocrates and Galen, who described it as a remedy for sleep disturbances and nervous complaints. In medieval European apothecary practice, the dried root was administered as decoctions, tinctures, and extracts for "nervousness," palpitations, and anxiety. It remains listed in the pharmacopoeias of several European countries.

Scientific Evidence

Valerian's particular advantage appears to be its dual action on both sleep and anxiety, which matters for people whose anxiety manifests primarily at night. Valerian and ashwagandha, for example, act through different primary mechanisms — GABA modulation versus cortisol and stress-axis regulation — which suggests they may complement each other.

A review of medicinal plants for anxiety and insomnia (Thieme, 2021) concluded that more clinical trials with an adequate, standardized design are necessary; however, the three plants with the most clinical potential are valerian, passionflower, and ashwagandha, with the combination of valerian with hops and passionflower giving the best results in clinical tests.

Evidence strength: Preliminary to moderate for sleep; limited and inconsistent for anxiety as a standalone agent. Combination formulas (e.g., valerian + hops, valerian + passionflower) show more consistent results in clinical trials.

4.6 Passionflower (Passiflora incarnata)

Traditional Use

Indigenous peoples of the Americas used passionflower for centuries as a sedative and anxiolytic, particularly for insomnia and agitation. European colonists adopted the plant into their folk medicine in the 17th century, and it subsequently entered official European pharmacopoeias as a recognized remedy for nervous restlessness. Preparations included teas of dried aerial parts, tinctures, and fluid extracts.

Scientific Evidence

Strong evidence exists for the use of herbal supplements containing extracts of passionflower as treatments for anxiety symptoms and disorders. Passionflower has shown promise in head-to-head comparisons with low-dose oxazepam (a benzodiazepine) for generalized anxiety, with comparable efficacy but fewer side effects in one small trial published in the Journal of Clinical Pharmacy and Therapeutics.

An anxiolytic effect was also seen in two other patient subsets: those undergoing surgery (n = 60) who were treated with passionflower monotherapy, and those diagnosed with adjustment disorder with anxious mood (n = 182) who were treated with passionflower in combination with other botanicals. Mild adverse events were reported in only one study, including dizziness, drowsiness, and confusion. This preliminary evidence suggests that passionflower may have a role in the treatment of anxiety and warrants future research.

Evidence strength: Preliminary to moderate. A small number of clinical trials, including one active-comparator RCT versus oxazepam, show significant anxiolytic effects. Study populations and preparations vary, limiting generalizability.

4.7 Omega-3 Fatty Acids (EPA and DHA)

Traditional Use

High consumption of fatty fish — rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) — has characterized the traditional diets of Nordic, Japanese, and coastal Mediterranean populations for millennia, and has been empirically associated with calm temperament and longevity in these cultures. No specific preparation for nervous complaints existed historically; rather, omega-3-rich foods were consumed as part of general dietary patterns.

Scientific Evidence

A randomized, double-blind, placebo-controlled trial found that omega-3 supplementation resulted in notable psychological and cognitive improvements, suggesting its potential as a safe and effective adjunct for managing stress, mood disorders, and sleep disturbances among participants with psychological distress.

Some studies have shown that omega-3 may have the potential to help with depression and anxiety, although results are mixed. Some studies have shown a significant impact and reduction in depressive symptoms while others have shown minimal impact or less. This is likely because every person's depression and symptoms are different, as is their baseline nutritional status, physiology, and more.

Evidence strength: Preliminary; the evidence is mixed and largely indirect. Omega-3 fatty acids have a strong role in neuronal membrane integrity and neurotransmission, but direct anxiolytic effects in adequately powered RCTs remain inconsistent.

4.8 B Vitamins

Traditional Use

No distinct traditional herbal use exists for isolated B vitamins; rather, cultures have long associated nutrient-dense foods (liver, whole grains, legumes, fermented foods) with mental vigor and resilience. The formal identification of B vitamins and their role in neurological function dates to the 20th century.

Scientific Evidence

B-group vitamins (B1, B2, B3, B5, B6, B8, B9, B12) and magnesium contribute to normal psychological function and normal functioning of the nervous system, supporting stress management and sleep quality. A balanced B complex can support neurotransmitter production — including serotonin, dopamine, and GABA — and energy metabolism. Vitamin B6 (pyridoxine) specifically acts as a cofactor in the enzymatic synthesis of GABA and serotonin from their precursors. Animal and clinical studies suggest complementary effects of magnesium and high-dose pyridoxine (vitamin B6) on stress reduction.

Evidence strength: Supportive but largely indirect. B vitamins fulfill cofactor roles in neurotransmitter biosynthesis; evidence for anxiolytic supplementation as a standalone intervention is limited in those without established deficiency.

4.9 Probiotics and the Gut-Brain Axis

Traditional Use

Fermented foods — yogurt, kefir, miso, kimchi, and sauerkraut — have featured prominently in traditional diets across Asia, Eastern Europe, and the Middle East. Their consumption has been associated in folk traditions with digestive comfort and emotional balance, reflecting an empirical understanding of gut-mood connections long before the microbiome was formally characterized.

Scientific Evidence

The consumption of probiotics was demonstrated to have a positive impact on alleviating stress responses, symptoms of anxiety and depression, and cognitive functions in both clinical and animal studies. Given current evidence, named strains (LGG, PS128, B. longum 1714) and prebiotics (GOS, inulin-type fructans) are plausible adjuncts for individuals with stress-related symptoms or subthreshold mood concerns, particularly when embedded in fiber-rich, Mediterranean-style dietary patterns. Effects should be framed as modest and mechanism-guided, attending to strain/substrate specificity, duration (≥4–8 weeks in many trials), and baseline diet/microbiome.

Evidence strength: Emerging. Strain-specific effects are demonstrated in individual trials, but large-scale, well-controlled clinical evidence for calming/anxiolytic effects remains preliminary.

5. Dietary and Lifestyle Factors

5.1 Dietary Patterns

There is growing research interest in overall dietary quality as a modulator of stress resilience and capacity for relaxation. Fiber-rich, Mediterranean-style dietary patterns are highlighted in the gut-microbiome literature as supportive of microbiota composition associated with better stress outcomes. Diet might play a role in the development of mental disorders and sleep quality. Foods naturally rich in magnesium (dark leafy greens, pumpkin seeds, almonds, black beans), omega-3 fatty acids (oily fish, flaxseed, walnuts), and fermented foods are emphasized in nutritional approaches to supporting calm.

5.2 Physical Exercise

The importance of physical activity comes from the evidence that it provides people with physical and mental health benefits like improved functional capacity, decreased risks of diseases, improved body composition, weight loss, improved mood, and reduced depression and anxiety.

5.3 Mindfulness Meditation and Mind-Body Practices

Mindfulness exercises that include breathing and visualizations as well as positive mind-body connections based on intention and affirmations have been demonstrated to reduce burdens of work-related stress and anxiety, and improve self-image. Mindfulness meditation programs show small improvements in anxiety, depression, and pain with moderate evidence, and small improvements in stress and health-related quality of life with low evidence when compared to nonspecific active controls.

One study explored the potential influence of long-term, regular meditation on the gut microbiota. Participants who practiced meditation exhibited distinct changes in the composition of their gut microbiota compared to a control group, suggesting that mindfulness practices can have a beneficial impact on gut health. Despite the growing understanding of the gut-brain-microbiome axis, researchers face challenges in studying the relationship between mood and the microbiome due to the myriad of factors involved.

5.4 Sleep Hygiene

Sleep is both a consequence and a contributor to the physiological state of relaxation. Anxiety may contribute to nightmares or insomnia, and sleep deprivation can also elevate the risk of an individual developing an anxiety disorder. Evidence-based sleep hygiene recommendations discussed in the literature include maintenance of consistent sleep schedules, limitation of exposure to blue light before sleep, and avoidance of caffeine in the hours preceding sleep.

5.5 Caffeine and Alcohol

Caffeine is a well-characterized adenosine receptor antagonist that promotes alertness by blocking the brain's natural signal for sleepiness and calm. It acts in direct opposition to GABAergic and adenosinergic relaxation mechanisms. The literature advises minimizing caffeine intake in the afternoon and evening hours for individuals with anxiety. Alcohol, while sometimes perceived as an acute anxiolytic, disrupts sleep architecture and has been associated with rebound anxiety, particularly with regular use.

6. Summary of Evidence by Ingredient

• Magnesium: Suggestive but methodologically variable evidence for anxiety reduction, especially in deficiency states. Biological mechanisms (NMDA antagonism, GABAergic modulation) are well-characterized.
• L-Theanine: Replicable EEG alpha-wave induction; moderate evidence for acute stress reduction at 200–400 mg; larger long-term trials needed.
• Ashwagandha (Withania somnifera): Moderate-to-strong evidence from multiple RCTs and meta-analyses for cortisol reduction and anxiety symptom improvement; long-term safety requires further study.
• Lavender (Silexan): Among the strongest botanical evidence bases; multiple RCTs demonstrate efficacy for GAD comparable to pharmaceutical comparators; approved OTC in Germany.
• Valerian (Valeriana officinalis): Preliminary to moderate evidence, primarily for sleep-associated anxiety; combination formulas show best results.
• Passionflower (Passiflora incarnata): Preliminary to moderate; one active-comparator RCT versus oxazepam is promising; additional well-designed trials needed.
• Omega-3 Fatty Acids (EPA/DHA): Mixed clinical evidence; strong mechanistic rationale; safe profile supports use as adjunct.
• B Vitamins: Supportive cofactor roles; direct anxiolytic evidence is limited in non-deficient populations.
• Probiotics: Emerging; strain-specific effects demonstrated; large-scale trials required.

References

• StatPearls / NCBI Bookshelf: Physiology, Stress Reaction
• Cleveland Clinic: HPA Axis — The Stress Response System
• Current Psychiatry Reports: Influence of the HPA Axis on Anxiety-Related Processes (2025)
• Cleveland Clinic: Gamma-Aminobutyric Acid (GABA)
• PMC: Neurotransmitters Regulation and Food Intake — The Role of Dietary Sources in Neurotransmission
• PMC / Nutrients: The Effects of Magnesium Supplementation on Subjective Anxiety and Stress — A Systematic Review
• PMC: Superiority of Magnesium and Vitamin B6 over Magnesium Alone on Severe Stress — A Randomized, Single-Blind Clinical Trial
• PMC: Examining the Effects of Supplemental Magnesium on Self-Reported Anxiety and Sleep Quality — A Systematic Review (2024)
• PMC: Magnesium Status and Stress — The Vicious Circle Concept Revisited
• PMC: Nutritional and Herbal Supplements for Anxiety and Anxiety-Related Disorders — Systematic Review
• PubMed: Effects of Ashwagandha (Withania somnifera) on Stress and Anxiety — Systematic Review and Meta-Analysis (2024)
• PMC / BJPsych Open: Effects of Ashwagandha Supplements on Cortisol, Stress, and Anxiety Levels in Adults — Systematic Review and Meta-Analysis (2025)
• SAGE Journals: Dual Impact of Ashwagandha — Significant Cortisol Reduction but No Effects on Perceived Stress (2025)
• PMC: Withania somnifera (Ashwagandha) Supplementation — A Review of Mechanisms, Health Benefits, and Role in Sports Performance (2025)
• PMC: A Comprehensive Review on Anxiolytic Effect of Lavandula angustifolia in Clinical Studies
• International Journal of Neuropsychopharmacology: Lavender Oil Preparation Silexan is Effective in Generalized Anxiety Disorder (2014)
• ScienceDirect: Multi-Center Double-Blind Randomised Study of Silexan vs. Lorazepam for GAD
• Scientific Reports: Efficacy and Safety of Lavender Essential Oil (Silexan) — Network Meta-Analysis (2019)
• PMC: Efficacy of Silexan in Subthreshold Anxiety — Meta-Analysis
• PMC: Silexan in Anxiety, Depression, and Related Disorders — Pharmacological Background and Clinical Data (2025)
• PMC: Lavender Oil — Potent Anxiolytic Properties via Modulating Voltage Dependent Calcium Channels
• Thieme: Medicinal Plants for Insomnia Related to Anxiety (2021)
• PubMed: L-theanine — From Tea Leaf to Trending Supplement (2025)
• PMC: L-theanine — Does the Science Match the Hype for Brain Health and Relaxation?
• PMC: Anti-Stress, Behavioural and Magnetoencephalography Effects of an L-Theanine-Based Nutrient Drink — Randomised Double-Blind Placebo-Controlled Crossover Trial
• PMC: Safety and Efficacy of AlphaWave® L-Theanine Supplementation for 28 Days — Randomized Double-Blind Placebo-Controlled Trial
• PMC: Promising, but Not Completely Conclusive — The Effect of L-Theanine on Cognitive Performance Based on Systematic Review and Meta-Analysis
• ScienceDirect: Effects of Omega-3 Supplementation on Stress, Anxiety, Depression, Sleep Quality — Randomized Double-Blind Placebo-Controlled Trial (2025)
• PMC: The Gut Microbiome and Its Impact on Mood and Decision-Making — A Mechanistic and Therapeutic Review
• PMC: Gut Microbiota Associated With Effectiveness and Responsiveness to Mindfulness-Based Cognitive Therapy in Improving Trait Anxiety
• ScienceDirect: Regulation of the Gut Microbiota Through Meditation and Exercise (2025)
• Open Access Journals: The Neurobiology of Anxiety Disorders
• MDPI Nutrients: The Effects of Magnesium Supplementation on Subjective Anxiety and Stress — A Systematic Review (2017)
• MDPI Pharmaceuticals: Efficacy and Safety of Herbal Supplements with Anxiolytic, Antidepressant, and Sedative Action (2026)
• PMC: Involvement of the GABAergic System in PTSD and Its Therapeutic Significance