It was suggested that the oral intake of L-Theanine could cause anti-stress effects via the inhibition of cortical neuron excitation.

Study results suggest that L-Theanine and caffeine, in combination, are beneficial for improving performance on cognitively demanding tasks.

Caffeine supplementation showed a significant ergogenic effect on muscle endurance and maximum strength in the bench press exercise.

This study suggests that caffeine could be considered as a supplementation strategy for female athletes competing in team sports.

Study findings suggest that L-Theanine has the potential to promote mental health in the general population with stress-related ailments and cognitive impairments.

The intake of a low/moderate dose of caffeine before and/or during exercise can improve self-reported energy, mood, and cognitive functions, such as aattention; it may also improve simple reaction time, choice reaction time, memory, or fatigue, however, this may depend on the research protocols.

The intake of a low/moderate dose of caffeine before and/or during exercise can improve self-reported energy, mood, and cognitive functions, such as attention; it may also improve simple reaction time, choice reaction time, memory, or fatigue. However, this may depend on the research protocols.

Coffee and caffeine consumption are significantly associated with decreased risk of depression.

M. chamomilla L. may produce clinically meaningful effects in addition to its anxiolytic activity in subjects with GAD and comorbid depression.

Melatonin intervention in subjects with Respiratory diseases, Metabolic disorders, and sleep disorders significantly affects sleep quality.

Lavender essential oil increased quality of sleep and reduced level of anxiety in patients with coronary artery disease.

A study suggests that the use of Chicory promotes a pro-apoptotic activity, an anti-inflammatory, antimicrobial, antioxidant, hypolipidemic, and hypoglycemic effect, and also an important role in appetite regulation.

Curcumin appears to be safe, well-tolerated, and efficacious among depressed patients. More robust randomized controlled trials with larger sample sizes and follow-up studies carried out over a longer duration should be planned to ascertain its benefits.

The standardized extract of A. paniculata with the right phytochemical composition of diterpenic labdanes is likely to have tremendous potential for developing hepatoprotective medicine.

Scientific evidence suggests that there is pharmacological solid potential in developing P. niruri as a drug to be used in liver disorders and antiviral therapy.

Perioperative melatonin may reduce the incidence of delirium in older adults in the included studies. While optimal dosing remains an unanswered question, the potential benefit of melatonin and melatonin receptor agonists may make them a reasonable option for delirium prevention in older adults undergoing surgical procedures.

This review highlights lion's mane's neuroprotective effects, driven by hericenones and erinacines. Erinacine A is the only known compound shown to cross the blood-brain barrier and stimulate nerve growth factor (NGF), supporting neuron survival and regeneration. It also cites a landmark double-blind clinical trial where lion's mane significantly improved cognitive function in adults with mild cognitive impairment, with benefits declining after supplementation stopped, making it one of the few mushrooms supported by direct human cognitive evidence.

This pharmacological review identifies Hericium erinaceus as a promising natural option for anxiety, depression, and cognitive decline. Its bioactive compounds support mood and brain health by regulating neurotransmitters, stimulating neurogenesis, increasing NGF and BDNF, and reducing oxidative stress and neuroinflammation. The authors conclude it offers a favorable risk-benefit profile for mild-to-moderate mood disorders, particularly stress-related cognitive decline and anxiety.

This narrative review evaluates the human evidence for Cordyceps as an energy and performance supplement. Traditionally used to reduce fatigue and support physical performance, its effects are linked to cordycepin, polysaccharides, and nucleosides. While animal studies consistently show improvements in exercise capacity and ATP production, the authors conclude that current human evidence remains limited and mixed, preventing firm conclusions about its performance-enhancing effects.

This review highlights the pharmacological benefits of maitake and shiitake mushrooms. Maitake's beta-glucans are linked to immune, anti-inflammatory, anti-allergic, and neuroprotective effects, while shiitake's lentinan is recognized as one of the most studied mushroom immunomodulators. Both have a long history of medicinal use and show promise for supporting immune function and reducing chronic stress and inflammation through cytokine regulation and macrophage activation.

This randomized controlled trial in 40 healthy men found that AHCC, a standardized shiitake mycelia extract, helped restore immune balance after antibiotic use. Supplementation promoted anti-inflammatory immune responses by modulating T regulatory and dendritic cells, providing direct human evidence that shiitake compounds support immune function and resilience.

This 12-week randomized controlled trial in 64 women found that 1,000 mg/day of low-molecular-weight collagen peptides significantly improved skin hydration, elasticity, and wrinkles compared to placebo. Benefits appeared within 6 weeks, with hydration improving up to 7 times more than placebo. The effects are attributed to bioactive collagen peptides that stimulate collagen, elastin, and hyaluronic acid production while reducing collagen breakdown.

This 180-day multicenter randomized controlled trial in 191 patients with knee osteoarthritis found that 40 mg/day of undenatured type II collagen (UC-II) significantly reduced pain, stiffness, and improved physical function compared to both placebo and glucosamine + chondroitin. UC-II users also required less rescue pain medication, while glucosamine + chondroitin showed no significant benefit over placebo.

Vitamin E is the skin's primary fat-soluble antioxidant, protecting against UV-induced oxidative damage. Research shows that UV exposure rapidly depletes vitamin E levels, while supplementation, especially when combined with vitamin C, helps restore antioxidant defenses, reduce oxidative stress and inflammation, and improve protection against sun-induced skin damage.

This comprehensive review highlights oysters as the richest dietary source of zinc, a mineral essential for testosterone production, sperm quality, motility, and fertility. It explains that zinc actively regulates key reproductive processes through molecular signaling pathways, with fertile men consistently showing higher zinc levels than infertile men, supporting its critical role in male reproductive health.

This multicenter randomized controlled trial evaluated 40 mg/day of zinc supplementation in men with hypogonadotropic hypogonadism. While zinc did not significantly outperform standard treatment, it reinforced zinc's essential role in testosterone production, spermatogenesis, and male reproductive health, with a trend toward earlier sperm production in the supplemented group.

This review highlights Cordyceps' traditional use for boosting energy, endurance, vitality, and sexual health. Its bioactive compound, cordycepin, may support ATP production and oxygen utilization, contributing to both energy and reproductive function. However, the authors note that evidence for testosterone and libido benefits in humans remains limited, with most supporting data coming from animal studies.

This foundational review identifies shilajit as a fulvic acid–rich natural compound traditionally used to enhance vitality, virility, and reproductive health. It also highlights its antioxidant, anti-inflammatory, antidiabetic, anxiolytic, and energy-supporting properties. The authors emphasize that while human clinical evidence is still limited, purified shilajit is essential to ensure safety and avoid heavy metal contamination.

This human clinical study found that 500 mg/day of purified shilajit for 8 weeks significantly increased the expression of genes involved in muscle repair and regeneration, including collagen and elastin. Supplementation was well tolerated with no adverse effects, providing the first molecular evidence in humans that shilajit is biologically active at clinically relevant doses and supports its traditional use for vitality and physical performance.

This randomized, double-blind, placebo-controlled trial in 40 IBS patients found that Bacillus coagulans (6 billion CFU/day) significantly improved bloating, abdominal pain, bowel habits, nausea, and other digestive symptoms compared to placebo. By the end of the study, 63% of participants were symptom-free versus 21% on placebo. The probiotic also improved anxiety and quality of life, with no reported adverse events.

This comprehensive review shows that bromelain supports digestive health by breaking down dietary proteins, reducing gut inflammation, and potentially promoting a healthy gut microbiota. Active throughout much of the digestive tract, it may be especially beneficial for people with impaired protein digestion. The authors note that the strongest digestive benefits have been observed at doses higher than those used in this formulation.

This meta-analysis of 6 randomized controlled trials (312 patients) found that bromelain significantly reduced pain and the need for rescue pain medication after surgery. Its anti-inflammatory effects are driven by inhibition of bradykinin and prostaglandins, mechanisms that may also help reduce inflammation in the digestive tract and support digestive health.

This comprehensive review explains how gut dysbiosis can contribute to anxiety and depression through the gut-brain axis by promoting inflammation, disrupting serotonin production, reducing beneficial short-chain fatty acids, and increasing neuroinflammation. It concludes that probiotics, prebiotics, and synbiotics, including Bacillus species, are evidence-based strategies for supporting gut-brain health and improving mood-related symptoms.

This landmark randomized controlled trial in 144 women with unexplained fatigue found that 80 mg/day of iron significantly reduced fatigue compared to placebo after four weeks. Benefits were limited to women with low iron stores (ferritin ≤50 μg/L), showing that even mild iron deficiency can contribute to fatigue and respond to supplementation.

This Cochrane review of 67 randomized controlled trials involving 8,506 women found that iron supplementation significantly increased hemoglobin levels, reduced the risk of iron deficiency and anemia, improved exercise performance, and decreased fatigue. While gastrointestinal side effects were the main drawback, ferric saccharate is generally better tolerated than many other iron forms.

This comprehensive review of 125 human studies found that iron deficiency is a major nutritional cause of hair loss, particularly telogen effluvium, with ferritin levels below 40 ng/mL commonly associated with increased shedding. The authors recommend iron supplementation for individuals with hair loss and low iron stores, and also note that folate deficiency may contribute to changes in hair, skin, and nails.

This randomized, double-blind, placebo-controlled crossover trial in 34 healthy adults found that 200 mg of L-theanine significantly reduced stress and lowered cortisol levels following a cognitive stress test. Brain imaging also showed increased alpha-wave activity, supporting a relaxed but alert mental state. These effects are linked to L-theanine's ability to modulate GABA, dopamine, and glutamate without causing sedation.

This 8-week randomized, double-blind, placebo-controlled trial in 40 adults found that a combination of Lactium and L-theanine significantly improved sleep duration, sleep efficiency, time to fall asleep, and nighttime awakenings. Supplementation also increased beneficial gut bacteria linked to better sleep quality, with no reported adverse effects.

This review and a landmark 2022 randomized controlled trial show that vitamin B6 plays a key role in the production of GABA, serotonin, and dopamine, neurotransmitters essential for mood and relaxation. Supplementation with high-dose vitamin B6 significantly reduced anxiety in healthy adults, while standard doses help support normal neurotransmitter synthesis and healthy nervous system function.

This authoritative review explains that iron is essential not only for red blood cell production but also for healthy immune function. It describes how inflammation can reduce iron availability, impairing erythropoiesis and contributing to anemia, while highlighting iron's key role in supporting both oxygen transport and immune cell activity.