Research
GABA
37 peer-reviewed studies curated from PubMed and Semantic Scholar.
Studies
Sorted by quality and recency
Clinical Presentations and Treatment of Phenibut Toxicity and Withdrawal: A Systematic Literature Review.
Systematic review of 62 cases from 36 studies on phenibut toxicity and withdrawal. Common symptoms of toxicity included altered mental status and psychosis, with 48.7% requiring intubation. Withdrawal symptoms included anxiety and insomnia, with benzodiazepines and other medications used for treatment. Highlights the potential dangers of phenibut use.
The effect of gamma-aminobutyric acid supplementation on growth performances, immune responses, and blood parameters of chickens reared under stressful environment: a meta-analysis.
Meta-analysis of 19 articles assessing the effects of gamma-aminobutyric acid (GABA) supplementation on growth performances, immune responses, and blood parameters in chickens under stress. GABA supplementation improved growth performance, with drinking water supplementation being more effective than dietary. Longer supplementation increased blood total protein and CD8+ count but reduced immunoglobulin and bursa's relative weight.
Safety and Tolerability of the Anxiolytic and Nootropic Drug Phenibut: A Systematic Review of Clinical Trials and Case Reports.
Systematic review of clinical trials and case reports on phenibut, a nootropic drug with anxiolytic effects. The review included 14 case reports of dependence and intoxication and 11 clinical trials with 583 patients. Clinical trials showed adverse events in 5.66% of patients, with somnolence being the most reported side effect. The review suggests phenibut is safe at therapeutic doses but highlights concerns about online-purchased phenibut and its potential for dependence.
γ-Aminobutyric Acid and Derivatives Reduce the Incidence of Acute Pain after Herpes Zoster - A Systematic Review and Meta-analysis.
This systematic review and meta-analysis assessed the effectiveness of GABA derivatives in preventing acute herpetic pain. It included three randomized controlled trials with a total of 297 patients, showing that the incidence of acute HZ pain events was significantly lower in the GABA group compared to the placebo group.
Effects of Oral Gamma-Aminobutyric Acid (GABA) Administration on Stress and Sleep in Humans: A Systematic Review.
Systematic review of 14 placebo-controlled human trials examining the effects of natural and biosynthetic oral GABA intake on stress and sleep. Results show limited evidence for stress reduction and very limited evidence for sleep benefits.
Production of Gamma-Aminobutyric Acid from Lactic Acid Bacteria: A Systematic Review.
Systematic review of gamma-aminobutyric acid (GABA) production by lactic acid bacteria (LAB). Discusses GABA-producing LAB species, biosynthesis pathways, and enhancement strategies for GABA production, including culture optimization and genetic engineering.
Efficacy of Food Supplement Based on Monacolins, γ-Oryzanol, and γ-Aminobutyric Acid in Mild Dyslipidemia: A Randomized, Double-Blind, Parallel-Armed, Placebo-Controlled Clinical Trial.
A randomized, double-blind, placebo-controlled trial evaluated the efficacy of a food supplement containing monacolins, γ-oryzanol, and γ-aminobutyric acid in subjects with mild dyslipidemia. The supplement reduced low-density lipoprotein cholesterol and total cholesterol while increasing high-density lipoprotein cholesterol, shifting subjects from very high to moderate cardiovascular disease risk without affecting glucose metabolism or hepatic and renal parameters.
Effects of γ-aminobutyric acid supplementation on glucose control in adults with prediabetes: A double-blind, randomized, placebo-controlled trial.
Double-blind, randomized, placebo-controlled trial investigating the effects of 500 mg GABA supplementation 3 times daily for 95 days on glucose control in 52 adults with prediabetes. The study found no significant change in postprandial glucose response or other markers of glycemic control and cardiovascular health compared to placebo.
A systematic review of phenibut withdrawal focusing on complications, therapeutic approaches, and single substance versus polysubstance withdrawal.
This systematic review characterizes the natural history of phenibut withdrawal and summarizes treatment strategies. It includes 25 case reports or conference abstracts, all involving male patients. Withdrawal symptoms can be severe, including delirium, hallucinations, and seizures. Benzodiazepines and baclofen are commonly used for symptom management, but there is no standard treatment.
A randomized trial of oral gamma aminobutyric acid (GABA) or the combination of GABA with glutamic acid decarboxylase (GAD) on pancreatic islet endocrine function in children with newly diagnosed type 1 diabetes.
A randomized trial in 97 children with newly diagnosed type 1 diabetes evaluated the safety and efficacy of oral GABA alone or in combination with GAD on pancreatic islet endocrine function. The primary outcome of preserving insulin secretion was not achieved, but the combination reduced serum glucagon levels. GABA was confirmed to be safe and tolerable.
Effects of regular-fat and low-fat dairy consumption on daytime ambulatory blood pressure and other cardiometabolic risk factors: a randomized controlled feeding trial.
This randomized controlled feeding trial assessed the effects of low-fat milk and regular-fat cheese enriched in GABA on daytime ambulatory blood pressure and cardiometabolic risk factors in 55 healthy individuals. The study found no significant differences in blood pressure between diets, but the cheese diet increased LDL-cholesterol and triglycerides compared to the control and milk diets.
Long-term gamma-aminobutyric acid (GABA) treatment fails to regain beta-cell function in longstanding type 1 diabetes in a randomized trial.
This phase I/II randomized controlled trial assessed the safety and efficacy of long-term treatment with a controlled-release oral GABA formulation in adults with long-standing type 1 diabetes. Thirty-five male subjects were randomized into three arms receiving different doses of GABA, with or without alprazolam, for 6 months. No effects were observed on fasting- or stimulated C-peptide levels, CGM metrics, or HbA1c, and hypoglycemic hormonal counter-regulation was unaltered. Safety concerns included elevated aspartate aminotransferase (AST) in some subjects.
Effects of combined gamma aminobutyric acid supplementation and exercise training on the body composition of women: A randomized double-blind trial.
Randomized, double-blind, placebo-controlled trial investigating the effects of GABA supplementation and exercise on body composition and physical performance in 26 women with obesity. GABA supplementation improved sit-up performance and reduced BMI and waist circumference, with no adverse effects on nutritional or serum parameters.
Effects of the PREMEN-CALM® in the Management of the Premenstrual Syndrome: A Randomized, Double-Blind, Placebo-Controlled Pilot Study.
A randomized, double-blind, placebo-controlled pilot study tested the effectiveness of the phytotherapeutic dietary supplement PREMEN-CALM (containing gamma-aminobutyric acid, vitamin B6, and melatonin) in managing premenstrual syndrome. The study found significant improvements in antioxidant status, mood state profile, and affective symptoms within the supplement group, though no statistical differences were observed between groups, suggesting a possible placebo effect.
Effect of Single Oral Coingestion of GABA and Malic Acid on Postprandial GLP-1, Glucose, and Insulin Responses in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study.
This randomized, double-blind, placebo-controlled, crossover study examined the effect of coingestion of GABA and malic acid on postprandial GLP-1, glucose, and insulin responses in 22 healthy adults. The coingestion significantly increased plasma GLP-1 levels compared to placebo, but there were no significant differences in postprandial blood glucose and insulin.
Effects of gamma-aminobutyric acid on working memory and attention: A randomized, double-blinded, placebo-controlled, crossover trial.
This randomized, double-blind, placebo-controlled, crossover trial tested the effects of 800mg GABA on visual working memory maintenance, spatial attention, and temporal attention in 32 healthy adults. GABA increased visual search time but did not affect visual search accuracy, temporal attention, or visual working memory precision.
The influence of a tomato food matrix on the bioavailability and plasma kinetics of oral gamma-aminobutyric acid (GABA) and its precursor glutamate in healthy men.
This study investigated the bioavailability of GABA and glutamate from tomatoes compared to a solution in water in 11 healthy men using a cross-over design. GABA from pureed tomatoes showed similar bioavailability to that of a solution in water, while glutamate absorption from tomatoes was slower. The findings suggest that GABA is bioavailable from tomatoes, indicating potential health effects similar to GABA supplements.
Dynamic Recovery: GABA Agonism Restores Neural Variability in Older, Poorer Performing Adults.
RCT examining the effect of GABA agonism on brain signal variability in 20 young and 24 older adults. GABA agonism increased brain signal variability in older adults to levels comparable to young adults, with the greatest effect in poorer performing older adults, suggesting potential for cognitive decline interventions.
The Improvement of Sleep by Oral Intake of GABA and Apocynum venetum Leaf Extract.
The study investigated the effects of GABA and Apocynum venetum leaf extract (AVLE) on sleep improvement in humans. GABA shortened sleep latency and AVLE increased non-REM sleep time. Simultaneous intake of both substances showed complementary effects on sleep quality.
The protective effect of γ-aminobutyric acid on the development of immune function in chickens under heat stress.
This study investigated the protective effect of GABA on immune function development in chicks under heat stress. GABA supplementation improved indices of thymus and bursa of fabricius, plasma levels of IL-2, IgA, IgG, IgM, ND antibody titres, and B and T lymphocyte subsets compared to the heat stress group.
[Effect of gamma-aminobutyric acid treatment on plasma substance P and calcitonin gene-related peptide levels in children with asthma].
RCT of 75 children with asthma comparing GABA treatment to control. GABA treatment significantly decreased plasma levels of substance P and calcitonin gene-related peptide after remission compared to control.
Anti-hypertensive effect of gamma-aminobutyric acid (GABA)-rich Chlorella on high-normal blood pressure and borderline hypertension in placebo-controlled double blind study.
RCT of 80 subjects with high-normal blood pressure and borderline hypertension comparing GABA-rich Chlorella to placebo for 12 weeks. GABA-rich Chlorella significantly decreased systolic blood pressure compared to placebo, with a tendency to decrease diastolic blood pressure. No adverse events were reported.
A double-blind, placebo-controlled, randomised-designed GABA tea study in children diagnosed with autism spectrum conditions: a feasibility study clinical trial registration: ISRCTN 72571312.
This double-blind, placebo-controlled study explored the effects of GABA Oolong tea on sensorimotor skills, ASC profiles, anxieties, and sleep in children with autism spectrum conditions. Significant improvements were observed in manual dexterity, balance, sensory responsivity, DSM-5 criteria, and cortisol levels with GABA tea. L-Theanine also showed improvements, though more sporadic.
[Bioequivalence of anvifen and phenibut].
An open randomized crossover test on 18 healthy volunteers studied the pharmacokinetics of anvifen (aminophenylbutyric acid) compared to phenibut tablets. The study found that anvifen and phenibut are bioequivalent in terms of pharmacokinetics.
Relaxation and immunity enhancement effects of gamma-aminobutyric acid (GABA) administration in humans.
Two studies investigated the effects of orally administered GABA on relaxation and immunity in humans. The first study with 13 subjects showed GABA increased alpha waves and decreased beta waves, indicating relaxation and reduced anxiety. The second study with 8 stressed volunteers showed GABA maintained higher IgA levels compared to placebo, suggesting enhanced immunity under stress.
Beneficial effect of GABA-rich fermented milk on insomnia involving regulation of gut microbiota.
Animal study evaluating the effects of GABA-rich fermented milk on anxiety and sleep quality in mice. High-dose GABA fermented milk decreased anxiety behavior and improved sleep parameters. The study also observed changes in gut microbiota and increased levels of short-chain fatty acids, suggesting a gut-related mechanism.
GABA Modulating Bacteria of the Human Gut Microbiota
The study used co-culture to isolate KLE1738, which required GABA for growth, and identified GABA-producing bacteria in the human gut microbiota. It found that the relative abundance of Bacteroides is negatively correlated with brain signatures associated with depression.
[The enhancement of human thermal resistance by the single use of bemitil and fenibut].
The study investigated the effects of single intake of bemitil and phenibut on thermal resistance, gas-energy exchange, blood oxygenation, and working capacity during intensive physical exertion. Both substances increased thermal resistance and maintained high working capacity, with phenibut showing the best protective effects.
Effect of acute and repeated administration of gamma aminobutyric acid (GABA) on growth hormone and prolactin secretion in man.
A study on the effects of a single oral dose of 5 g GABA on growth hormone and prolactin secretion in 19 subjects, with a placebo group of 18 controls. GABA significantly elevated plasma growth hormone levels but did not consistently alter plasma prolactin concentration. Repeated administration of 18 g GABA daily for 4 days blunted the growth hormone response and enhanced the prolactin response to insulin hypoglycemia.
Contributions of Gamma-Aminobutyric Acid (GABA) Produced by Lactic Acid Bacteria on Food Quality and Human Health: Current Applications and Future Prospects
This narrative review discusses the synthesis and food applications of GABA produced by lactic acid bacteria, highlighting its potential health benefits such as neuroprotection, improving sleep quality, alleviating depression, and anti-inflammatory effects. It also explores the potential of GABA-enriched foods for antidiabetic and antihypertension effects.
Gamma-aminobutyric acid (GABA): a comprehensive review of dietary sources, enrichment technologies, processing effects, health benefits, and its applications
This narrative review provides a comprehensive insight into the dietary sources, enrichment technologies, processing effects, and applications of gamma-aminobutyric acid (GABA) in the food industry. It summarizes the health benefits of GABA-enriched foods, including neuroprotection, anti-insomnia, anti-depression, anti-hypertensive, anti-diabetes, and anti-inflammatory effects.
United States Pharmacopeia (USP) Safety Review of Gamma-Aminobutyric Acid (GABA)
The United States Pharmacopeia conducted a safety evaluation of GABA as a dietary supplement, assessing clinical studies, adverse events, and toxicology data. No serious adverse events were associated with GABA at intakes up to 18 g/d for 4 days and 120 mg/d for 12 weeks. Some studies showed a transient and moderate drop in blood pressure. Caution is advised for pregnant and lactating women due to potential effects on neurotransmitters and the endocrine system.
GABA and l-theanine mixture decreases sleep latency and improves NREM sleep
Animal study investigating the synergistic sleep enhancement effect of a GABA/l-theanine mixture. The mixture decreased sleep latency and increased sleep duration, REM, and NREM sleep compared to GABA or theanine alone. It also restored sleep time and quality in a caffeine-induced arousal model and increased expression of GABA and GluN1 receptor subunit.
Study of GABA in Healthy Volunteers: Pharmacokinetics and Pharmacodynamics
The study investigated the pharmacokinetics and pharmacodynamics of GABA in 12 healthy volunteers. GABA was rapidly absorbed and increased circulating insulin and glucagon levels, suggesting potential therapeutic benefits for diabetes. No significant changes in glucose levels were observed, and minor adverse events were reported.
Effect of γ-aminobutyric acid on digestive enzymes, absorption function, and immune function of intestinal mucosa in heat-stressed chicken.
The study investigated the effects of dietary γ-aminobutyric acid (GABA) on digestive enzyme activity, absorption function, and immune function of intestinal mucosa in heat-stressed Wenchang chickens. GABA administration alleviated the inhibitory effects of heat stress on these functions, with significant improvements observed in enzyme activity and immune markers over time.
Neurotransmitters as food supplements: the effects of GABA on brain and behavior
Narrative review discussing the effects of GABA as a food supplement on brain and behavior. The paper highlights the unclear mechanism of action and the need for further research to establish the effects of oral GABA administration on brain GABA levels and behavior.
A Gut Feeling about GABA: Focus on GABAB Receptors
The paper reviews the role of GABA and GABAB receptors in the gastrointestinal (GI) tract, highlighting their modulatory effects on intestinal motility, gastric functions, and potential inhibition of GI carcinogenesis. It discusses the potential of GABAB receptors as targets for treating GI disorders.