{"ok":true,"entry":{"slug":"glutamine","kind":"supplement","name":"glutamine","aliases":["L-glutamine"],"brands_sg":["California Gold Nutrition","NOW Foods","Doctor's Best","Thorne","Nutricost"],"class":"amino acid","tags":["fitness","gut"],"use_for":"little gain in training · one small trial in ibs","use_after":null,"use_duration":"recovery study used four 0.3 g/kg doses over 3 days","take_with":"in the ibs trial, alongside a low-fodmap diet","pros":["15–30 g a day showed no evidence of toxicity","no side effects reported in the exercise studies","one small trial: less soreness, faster recovery"],"cons":["nih: research does not support it for performance","45 g a day for 6 weeks changed nothing in lifters","gut evidence is one small 6-week ibs trial"],"dose_note":"an adult gets about 3–6 g a day from protein-containing foods; exercise studies used 0.9 g/kg lean body mass (almost 45 g a day) or four doses of 0.3 g/kg over 3 days, and an ibs trial used 15 g a day for 6 weeks; oral doses of 0.21–0.42 g/kg (15–30 g a day at 154 pounds) have shown no evidence of toxicity","dosage":{"ul":null,"unit":"g","fda_dv":null,"rda_ai":null,"ul_status":"none_established","population":"general adult","hsa_max_daily":null},"ul_status":"none_established","sg_class":null,"cautions":["colds and immunity — little research-based support","critical illness — glutamine is classed as essential in that group","not listed on hsa's prohibited/restricted annexes — that list is not exhaustive"],"clashes":[],"sources":[{"id":"nih_ods_glutamine_role","url":"https://ods.od.nih.gov/factsheets/ExerciseAndAthleticPerformance-HealthProfessional/","label":"NIH ODS — Dietary Supplements for Exercise and Athletic Performance (Health Professional), glutamine background","quote":"Glutamine is the most abundant amino acid in muscle, blood, and the body's free-amino-acid pool … an adult consumes about 3–6 g/day in protein-containing foods … It is an EAA for critically ill patients","accessed":"2026-08-27"},{"id":"nih_ods_glutamine_strength","url":"https://ods.od.nih.gov/factsheets/ExerciseAndAthleticPerformance-HealthProfessional/","label":"NIH ODS — Exercise and Athletic Performance, glutamine and strength training","quote":"There were no significant differences between the two groups in measures of strength, torque, or lean tissue mass, demonstrating that glutamine had no effect on muscle performance, body composition, or muscle-protein degradation","accessed":"2026-08-27"},{"id":"nih_ods_glutamine_recovery","url":"https://ods.od.nih.gov/factsheets/ExerciseAndAthleticPerformance-HealthProfessional/","label":"NIH ODS — Exercise and Athletic Performance, glutamine and recovery from eccentric exercise","quote":"glutamine (four doses of 0.3 g/kg body weight over 3 days) … Supplementation with glutamine reduced the magnitude of strength loss, accelerated strength recovery, and diminished muscle soreness more quickly than placebo; these effects were more pronounced in the men","accessed":"2026-08-27"},{"id":"nih_ods_glutamine_immune","url":"https://ods.od.nih.gov/factsheets/ExerciseAndAthleticPerformance-HealthProfessional/","label":"NIH ODS — Exercise and Athletic Performance, glutamine and immune function","quote":"Some athletes use glutamine supplements in the hope that they will attenuate exercise-induced immune impairment and reduce their risk of developing upper respiratory tract infections. However, there is little research-based support for this benefit","accessed":"2026-08-27"},{"id":"nih_ods_glutamine_safety","url":"https://ods.od.nih.gov/factsheets/ExerciseAndAthleticPerformance-HealthProfessional/","label":"NIH ODS — Exercise and Athletic Performance, glutamine safety","quote":"the glutamine had no reported side effects … Daily oral doses ranging from 0.21 to 0.42 g/kg body weight glutamine (equivalent to 15–30 g/day in a person weighing 154 pounds) have provided no biochemical or clinical evidence of toxicity","accessed":"2026-08-27"},{"id":"nih_ods_glutamine_verdict","url":"https://ods.od.nih.gov/factsheets/ExerciseAndAthleticPerformance-HealthProfessional/","label":"NIH ODS — Exercise and Athletic Performance, glutamine implications for use","quote":"The research to date does not support taking glutamine alone to improve exercise and athletic performance","accessed":"2026-08-27"},{"id":"glutamine_ibs2021","url":"https://europepmc.org/article/PMC/PMC8716871","label":"Glutamine Supplementation Enhances the Effects of a Low FODMAP Diet in Irritable Bowel Syndrome Management (Frontiers in Nutrition 2021, PMC8716871)","quote":"randomized to receive a low FODMAP diet either with glutamine (15 g/day) or a placebo for 6 weeks … the superiority of adding glutamine supplementation to a low FODMAP diet in amelioration of IBS symptoms","accessed":"2026-08-27"},{"id":"hsa_hs","url":"https://file.go.gov.sg/hsa-hs-guidelines.pdf","label":"HSA Health Supplements Guidelines (GL-CHPB-3-001 Rev. 020, January 2026), Tables 4–5","quote":"HS for use by the general adult population should not contain vitamins and minerals exceeding the stipulated limits stated in Tables 4 and 5","accessed":"2026-08-27"},{"id":"hsa_restricted","url":"https://file.go.gov.sg/hsa-chp-prohibited-restricted-ing-guidelines.pdf","label":"HSA Guidelines on Prohibited and Restricted Ingredients in Health Supplements and Traditional Medicines (Oct 2025), Annexes A/B","quote":"The objective of this guideline is to highlight the substances of concern when used in HS and TM and is not meant to be an exhaustive list","accessed":"2026-08-27"},{"id":"iherb_sg","url":"https://sg.iherb.com/c/l-glutamine","label":"iHerb Singapore — L-Glutamine category page (default sort, 110 results)","quote":"L-Glutamine … 1 - 48 of 110 results","accessed":"2026-08-27"}],"brand_certs":[{"brand":"Thorne","example":"Thorne® L-Glutamine Powder","programme":"NSF Certified for Sport","matching_products":2,"brand_total_certified":66}],"updated_at":"2026-08-30T17:59:38.376296+08:00"},"disclaimer":"kozen-x is not a medical device and does not give medical advice. it lists what published sources have written down. absence of a record is not the same as safe."}