The 2017 position stand from the International Society of Sports Nutrition (ISSN) reviews the safety and efficacy of creatine supplementation in exercise, sport, and clinical medicine. Creatine monohydrate supplementation increases intramuscular creatine and phosphocreatine stores by approximately 20 to 40%, improving high-intensity exercise capacity and training adaptations; typical baseline muscle creatine stores (~120 mmol/kg dry muscle) can approach an upper limit of ~160 mmol/kg. Standard dosing includes a loading phase of ~0.3 g/kg/day (commonly 5 g four times daily) for 5 to 7 days followed by maintenance dosing of 3 to 5 g/day, with some larger or intensely training athletes requiring 5 to 10 g/day; an alternative protocol is 3 g/day for ~28 days. Pediatric data reviewed include adolescent athletes studied for ergogenic effects using standard weight-based dosing, as well as infants, children, and adolescents with inborn creatine synthesis deficiencies treated therapeutically with higher doses (0.3 to 0.8 g/kg/day), including in infants <1 year of age, without clinically significant adverse effects. Across healthy and clinical populations ranging from infants to the elderly, short- and long-term supplementation up to 30 g/day for as long as 5 years is reported as safe and well tolerated, with weight gain as the only consistently reported side effect. The ISSN concludes that creatine monohydrate supplementation is acceptable for children and adolescent athletes when used under supervision, in the setting of serious or competitive training, with adequate nutrition, appropriate education, and adherence to recommended dosing. Importantly, they state that product label warnings against use under 18 years are legal precautions and likely unnecessary given the evidence supporting creatine’s safety in children and adolescents. [1]
Furthermore, a 2025 expert opinion by members of the ISSN and international creatine researchers addresses dietary creatine intake and creatine supplementation. Daily creatine turnover is approximately 2 to 4 g/day, with about half synthesized endogenously and the remainder obtained from dietary sources such as meat and fish. National Health and Nutrition Examination Survey (NHANES) analyses cited show that U.S. children and adolescents aged 2 to 19 years consume an average of ~1 g/day of creatine, and that higher dietary intake (>1.5 g/day) is associated with greater height, weight, lean mass, and bone mineral content and with lower fat mass and body fat percentage. Adequate intake values cited for infants are 7 mg/day for ages 0 to 6 months and 8.4 mg/day for ages 7 to 12 months. Additional pediatric clinical and observational data summarized in the review include use of creatine monohydrate in infants, children, and adolescents for creatine metabolism disorders, Duchenne muscular dystrophy, and acute lymphoblastic leukemia, with no clinically significant adverse effects reported. Across more than 680 clinical trials involving over 12,800 participants, ranging from infants to very elderly individuals, creatine supplementation has been administered at doses up to 30 g/day for periods extending up to 14 years, with no reported clinical adverse events and weight gain identified as the most consistent side effect; postmarketing surveillance data indicate creatine is rarely cited in adverse event reports (~0.0007%). The review also notes that creatine monohydrate dosing commonly used to increase tissue creatine includes ~0.3 g/kg/day for 5 to 7 days followed by 0.05 to 0.15 g/kg/day thereafter. The authors conclude that restricting access to creatine-containing products for children and adolescents is not supported by available scientific evidence and may reduce dietary creatine availability during periods of growth and maturation. [2]
A 2021 review evaluated the evidence on creatine supplementation in healthy pediatric and adolescent populations including 13 studies, comprising 268 participants with mean ages ranging from 11.5 to 18.2 years. Most studies were randomized controlled trials (>75%), and 85% involved soccer players or swimmers. Creatine dosing regimens most commonly included a loading phase of 0.3 g/kg/day for 7 days (39% of studies) or a fixed dose of 20 g/day (23%); only 31% of studies included a maintenance phase, typically 5 g/day for 22 to 49 days. Performance outcomes were inconsistent across studies, with some reporting improvements in sport-specific or anaerobic measures and others showing no difference versus placebo. One study in healthy non-athletic children aged 10 to 12 years found no effect on cognitive test performance after 0.3 g/kg/day for 7 days. Short-term physiologic findings included increases in total body water (~2.3 L) and body weight (~1 kg) after 7 days of supplementation in soccer players, without changes in homocysteine or creatine kinase. No renal or hepatic adverse effects were reported; however, no included studies were designed to formally assess safety and long-term safety data in adolescents. The review concludes that evidence for efficacy and safety of creatine supplementation in adolescents is limited and long-term effects on growth and development remain unknown, highlighting a need for higher-quality, longitudinal research. [3]
Another review evaluated creatine use in children and adolescents and reported that creatine supplementation in pediatric populations can increase intramuscular phosphocreatine and cellular energy status. One study demonstrated a 13.9% increase in skeletal muscle phosphocreatine and a 2.1% increase in brain phosphocreatine in children after 0.3 g/kg/day for 7 days, with smaller muscle responses than observed in elderly adults (22.7%) and similar or lower responses compared with adult omnivores (10.3%). In Duchenne muscular dystrophy, creatine 5 g/day for 8 weeks significantly increased the phosphocreatine/inorganic phosphate ratio compared with placebo (4.7 vs 3.3; p= 0.03), whereas lower-dose regimens (0.1 g/kg/day) in juvenile systemic lupus erythematosus and juvenile dermatomyositis did not increase phosphocreatine content. Across adolescent athlete studies, which were limited primarily to soccer and swimming, typical dosing included loading phases of 20 to 30 g/day or approximately 0.03 to 0.3 g/kg/day for 4 to 9 days, sometimes followed by maintenance dosing of 5 g/day. Several studies reported improvements in anaerobic power, sprint performance, or sport-specific tasks, while others reported no performance differences compared with placebo. Regarding safety, no pediatric or adolescent studies were designed with safety as a primary endpoint; however, no serious adverse events were reported across athletic or clinical studies, including trials that monitored renal and hepatic laboratory markers. Reported effects were limited to expected findings such as increases in body mass or total body water. Post-marketing surveillance identified 22 creatine-associated reports among 15,274 total adverse event reports (0.144%) from 2018 to 2020. Importantly, creatine monohydrate is designated as generally recognized as safe (GRAS) by the U.S. Food and Drug Administration, including for older children and adolescents. The review concludes that creatine appears well-tolerated in pediatric populations and may provide ergogenic and therapeutic benefits, although the supporting evidence is limited, and largely short-term. [4]