Supplemental GABA in the dose range of 20 to 300 mg (0.02–0.3 grams) has been used to improve sleep quality,^[1] mood,^[2] and markers of stress,^[1] while a dose of 800 mg (0.8 grams) has been used to improve attention.^[3] Some studies using daily GABA supplementation for 1–4 weeks have used a dosage range of 100 to 300 mg (0.1 to 0.3 grams) per day to improve sleep quality.^[1] A supplemental GABA dose in the range of 3,000–5,000 mg (3–5 grams) has been used to increase growth hormone concentrations.^[4][5][6]  However, due to a lack of clinical research, it is unclear if these dosages are optimal.