Creatine for Youth Athletes: Safety, Dosing, and the Evidence

The Youth Athlete Question

Surveys suggest that 5–20% of high school athletes in the United States have used creatine, with rates highest in football, wrestling, and hockey. Metzl et al. (2001) reported that creatine was the most commonly used supplement among high school athletes after protein powders and multivitamins. Use begins as early as middle school, often without parental knowledge or medical guidance.

The central question is not whether adolescents are using creatine — they are. The question is whether the available evidence supports or contradicts this practice. Most position statements from medical and sports organizations have cautioned against adolescent use, but the reasoning behind these cautions is worth examining in detail.

The concern is not toxicity. Creatine monohydrate has an exceptional adult safety profile across hundreds of studies and decades of use. The concern is the absence of long-term data specifically in developing bodies — a gap that persists because no one has funded multi-year creatine studies in children. This absence of evidence is not evidence of harm, but it is a legitimate basis for caution.

Safety Evidence in Adolescents

Direct safety data in adolescents are limited but uniformly reassuring where they exist. Unnithan et al. (2001) supplemented adolescent swimmers with creatine for 6 days and reported no adverse effects on kidney function, liver enzymes, or electrolyte balance. The sample was small, but the biochemical parameters were normal across all measures.

Mohebbi et al. (2012) studied creatine supplementation in adolescent soccer players over 7 days of loading followed by 7 weeks of maintenance dosing. No adverse effects were reported, and kidney function markers remained within normal ranges throughout. Body mass increased — consistent with the expected water retention effect — without reported gastrointestinal complaints.

Jagim et al. (2018) conducted one of the more thorough examinations of creatine in young athletes, studying 13–18 year old athletes. No clinically significant changes in metabolic or hematological markers were observed. The International Society of Sports Nutrition (ISSN) position stand (Kreider et al., 2017) noted that short-term creatine use in adolescents appears safe based on available data, while acknowledging the need for longer-term studies.

The safety concern that persists is the long-term unknown. No study has tracked creatine use from age 14 through age 30. This gap exists for virtually every dietary supplement and most food additives, but it carries particular weight for a substance taken by developing bodies. The counterpoint is that creatine is an endogenous compound — the body synthesizes approximately 1 g/day and obtains another 1–2 g/day from dietary meat and fish.

Performance Effects in Young Athletes

Performance studies in adolescents generally mirror adult findings, adjusted for maturation stage. Ostojic (2004) reported that creatine supplementation improved sprint performance and dribbling speed in elite junior soccer players over a 7-day loading period. The improvements were modest but consistent with the expected ergogenic effect on phosphocreatine-dependent tasks.

Yanez-Silva et al. (2017) found that creatine supplementation enhanced upper and lower body strength in adolescent swimmers during a 4-week concurrent training program. The creatine group gained significantly more in bench press and squat strength compared to placebo, with gains proportional to those seen in adult studies when adjusted for baseline strength levels.

The critical caveat: adolescent athletes often have more room for improvement through training alone than adult athletes do. A 15-year-old with two years of training experience will gain more from optimized programming, adequate nutrition, and sufficient sleep than from any supplement. The marginal benefit of creatine is smaller in absolute terms when the total improvement available through basic training is still large.

Importantly, no study has found creatine to be less effective in adolescents compared to adults on a body-weight-adjusted basis. The phosphocreatine system functions identically in adolescents and adults. The question is not efficacy — it is whether the benefit justifies supplementation in a population that may not need it yet.

Age-Appropriate Dosing

No adolescent-specific dosing protocol has been established through clinical trials. The most commonly used approach in research has been adult protocols applied to adolescents: a loading phase of approximately 0.3 g/kg/day for 5–7 days, followed by maintenance at 0.03–0.05 g/kg/day. For a 60 kg teenager, this means 18 g/day loading and 2–3 g/day maintenance.

Jagim et al. (2018) suggested that adolescents should skip the loading phase entirely and use a lower daily dose of 3–5 g/day, reaching saturation more gradually over 3–4 weeks. This approach reduces the likelihood of GI discomfort and avoids the rapid weight gain from water retention that can be alarming to parents and athletes unfamiliar with the mechanism.

Body mass scaling is particularly important in younger adolescents who may weigh substantially less than adults. A 45 kg 13-year-old taking a standard 5 g/day dose is receiving a higher relative dose (0.11 g/kg) than an 80 kg adult taking the same amount (0.06 g/kg). Adjusting to 0.05 g/kg/day — roughly 2–3 g/day for a lighter adolescent — is a more conservative approach that still achieves muscle creatine saturation over time.

Sport Organization Positions

The American Academy of Pediatrics (AAP) has discouraged the use of performance-enhancing supplements, including creatine, in athletes under 18. The AAP position (2016) is based primarily on the absence of long-term safety data in pediatric populations rather than on evidence of harm. The statement acknowledges that creatine has a favorable safety profile in adults.

The National Collegiate Athletic Association (NCAA) permits creatine use by college athletes but prohibits institutions from distributing it to athletes. This reflects an institutional liability concern rather than a safety determination. NCAA athletes who are 18+ can purchase and use creatine independently.

The International Society of Sports Nutrition (ISSN) position stand (Kreider et al., 2017) states that creatine monohydrate is the most effective ergogenic nutritional supplement and that younger athletes should consider it as an alternative to potentially dangerous anabolic androgenic drugs. This is a nuanced position: ISSN frames creatine not as a substance to fear but as a safer alternative in a sports culture where adolescents will seek performance enhancement regardless.

The National Strength and Conditioning Association (NSCA) has taken a similar pragmatic view, noting that creatine may be appropriate for post-pubertal athletes who are engaged in serious competitive training, consuming a well-balanced diet, and supervised by qualified professionals. The emphasis is on context: creatine supplementation in a 17-year-old varsity athlete under a strength coach's guidance is a different proposition than a 13-year-old self-dosing from a GNC purchase.

Growth and Development Concerns

A common parental concern is that creatine may interfere with growth, hormonal development, or puberty. No evidence supports these fears. Creatine does not alter testosterone, growth hormone, insulin-like growth factor 1 (IGF-1), or any other growth-related hormone. Volek et al. (2004) measured hormonal responses to creatine in young adults and found no changes in anabolic or catabolic hormone concentrations.

The confusion may arise from association with anabolic steroids in the public perception of sports supplements. Creatine is not a hormone, not a steroid, and does not interact with the endocrine system. It is a naturally occurring amino acid derivative found in meat, fish, and produced endogenously by the liver, kidneys, and pancreas.

Another concern is the effect on growth plates (epiphyseal plates) in adolescents who have not completed skeletal maturation. No mechanism by which creatine could affect growth plate biology has been proposed, and no study has reported growth plate abnormalities associated with creatine use. The weight gain from water retention (1–3 kg during loading) is sometimes misinterpreted as abnormal, but it resolves within 2–4 weeks of cessation.

Kidney function deserves specific mention. Parents frequently ask whether creatine damages developing kidneys. The answer, based on available evidence, is no — but the evidence is limited to short-term studies. Creatine supplementation increases serum creatinine (a creatine breakdown product used as a kidney function marker), which can produce a false-positive signal on standard blood tests. Clinicians should be aware that elevated creatinine in a creatine-supplementing adolescent does not necessarily indicate renal impairment. Cystatin C is a more reliable marker of kidney function in this context.

Parental Guidance Framework

For parents evaluating creatine for an adolescent athlete, the decision framework should address maturation, training stage, nutritional foundation, and supervision.

Maturation threshold: Most experts suggest that creatine supplementation is more appropriate for post-pubertal athletes (typically 16+) who have completed or nearly completed skeletal growth. Pre-pubertal or early-pubertal athletes have limited capacity for the type of high-intensity, phosphocreatine-dependent training that creatine targets. At younger ages, the supplement is unlikely to provide meaningful benefit.

Training prerequisite: Creatine amplifies the results of structured training. An adolescent who is not engaged in consistent, progressive resistance training or sport-specific conditioning will gain little from supplementation. The American College of Sports Medicine (ACSM) has emphasized that supplements should be considered only after training, nutrition, and recovery are optimized — a standard that most adolescent athletes have not yet reached.

Nutritional foundation: Many adolescent athletes have inadequate baseline nutrition: insufficient caloric intake, low protein consumption, erratic meal timing, and excessive reliance on processed foods. Addressing these fundamentals produces larger performance improvements than any supplement. A 16-year-old eating 2,000 calories with 60 g of protein needs a dietary overhaul, not a creatine supplement.

Supervision requirement: If creatine supplementation is pursued, it should occur under the guidance of a sports dietitian, team physician, or qualified strength coach who can monitor dosing, hydration, weight changes, and periodically assess kidney function. Unsupervised self-administration — which describes the majority of adolescent creatine use — eliminates the safety net that makes supplementation defensible.

References

1. Metzl JD, Small E, Levine SR, Gershel JC. Creatine use among young athletes. Pediatrics. 2001;108(2):421-425. PMID: 11483809.
2. Unnithan VB, Veehof SH, Vella CA, Kern M. Is there a physiologic basis for creatine use in children and adolescents? J Strength Cond Res. 2001;15(4):524-528. PMID: 11726268.
3. Mohebbi H, Rahmani-Nia F, Moghadasi M, Hajizadeh B. Effect of creatine supplementation on sprint and skill performance in young soccer players. Middle East J Sci Res. 2012;12(3):397-401.
4. Jagim AR, Stecker RA, Harty PS, Erickson JL, Kerksick CM. Safety of creatine supplementation in active adolescents and youth: a brief review. Front Nutr. 2018;5:115. PMID: 30547033.
5. Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18. PMID: 28615996.
6. Ostojic SM. Creatine supplementation in young soccer players. Int J Sport Nutr Exerc Metab. 2004;14(1):95-103. PMID: 15129933.
7. Yanez-Silva A, Buzzachera CF, Picon IDC, et al. Effect of low dose, short-term creatine supplementation on muscle power output in elite youth swimmers. J Int Soc Sports Nutr. 2017;14:16. PMID: 28572748.
8. Volek JS, Ratamess NA, Rubin MR, et al. The effects of creatine supplementation on muscular performance and body composition responses to short-term resistance training overreaching. Eur J Appl Physiol. 2004;91(5-6):628-637. PMID: 14685870.