Creatine is one of the most studied supplements in adults, with a strong safety record for people over 18. For children and adolescents, the picture is far less clear. The American Academy of Pediatrics does not recommend creatine for anyone under 18, primarily because there isn’t enough research to confirm it’s safe during growth and development. That said, the limited studies that do exist in adolescents have not found serious harm.
What Major Health Organizations Say
The AAP’s position is straightforward: until safety can be established in adolescents, creatine use should be discouraged. This recommendation isn’t based on evidence of harm. It’s based on the absence of evidence proving safety. No large, well-designed studies have been conducted specifically to test whether creatine causes problems in growing bodies, so the default medical stance is caution.
Despite this guidance, creatine use among young athletes is widespread. Middle school and high school athletes at all grade levels report taking it, often without medical supervision. That gap between official recommendations and real-world behavior is part of what makes this topic so important for parents to understand clearly.
Why Growing Bodies Raise Different Questions
In adults, creatine works by boosting the body’s short-term energy reserves in muscle cells, which helps with brief, high-intensity efforts like sprinting or lifting. Adult muscle mass is relatively stable, so the effects of creatine are predictable and well-documented.
Adolescents are different. Around puberty, teenagers experience rapid growth in lean muscle mass. During this critical window, the effects of adding creatine on top of natural growth aren’t well understood. Researchers at Nationwide Children’s Hospital have pointed out that the potential risks associated with changes in body composition during this period need further investigation. It’s not that something harmful has been observed. It’s that nobody has looked carefully enough to rule it out.
Children’s muscles also appear to handle their natural creatine-phosphate energy system differently than adults do. Research comparing children and adults during high-intensity exercise shows that kids have faster turnover of phosphocreatine in their muscles, possibly due to enhanced cellular energy production or lower baseline creatine stores. What this means for supplementation is still unresolved.
What the Existing Research Shows
A systematic review of creatine monohydrate supplementation in adolescent athletes examined studies lasting from 8 weeks to 32 weeks, with one group followed for seven years. Across these studies, no serious adverse events were attributed to creatine. Kidney function was evaluated in four studies, and none found clinically meaningful changes in markers like serum creatinine or filtration rate. Liver enzymes stayed within normal ranges in the athletic group that was tested. Long-term heart and metabolic outcomes showed no link between adolescent creatine use and high blood pressure, cholesterol problems, diabetes, or increased body mass index.
These findings are reassuring, but they come with an important caveat: none of these studies were specifically designed to look for adverse effects. They were primarily performance studies that happened to track some safety markers along the way. A study designed to find harm looks very different from one that simply doesn’t notice any.
Side Effects to Expect
The most common side effects of creatine at any age are gastrointestinal. In a 28-day supplementation study, roughly 79% of participants reported at least one gut-related symptom. The most frequent complaints were water retention (50%), bloating (up to 67% depending on dosing protocol), stomach discomfort (up to 58%), puffiness, and weight gain. These effects were generally mild and not medically serious, but they can be uncomfortable, especially for a teenager who may not understand why they suddenly feel heavier or puffy.
Weight gain from creatine is largely water retention in the muscles, not fat. For young athletes in weight-class sports like wrestling, or for kids who are already self-conscious about their bodies, this can create real problems even if it’s physiologically harmless.
The Bigger Picture for Young Athletes
One reason pediatricians urge caution isn’t just the supplement itself. It’s what reaching for supplements signals about a young athlete’s approach to training. Adolescents almost universally have more to gain from consistent training, proper nutrition, adequate sleep, and hydration than from any supplement. Creatine provides a modest performance edge in adults, typically a few percent improvement in power output during short bursts of effort. For a teenager whose body is still developing, those gains are likely smaller than what they’d get from eating enough protein and calories to support their growth.
There’s also a practical concern about supplement quality. Creatine products are not regulated the same way as medications, and contamination or mislabeling is a known issue in the supplement industry. A teenager buying a tub of creatine from a convenience store or online retailer may not be getting a pure product. If you do decide to allow creatine use, choosing a product with third-party testing certification reduces this risk.
What Parents Should Weigh
The honest summary is this: creatine has not been shown to be dangerous for adolescents in the studies that exist, but those studies are small, short, and weren’t designed to catch rare or long-term problems. The official medical recommendation is to avoid it under 18. The real-world data is cautiously reassuring but incomplete.
If your teenager is already taking creatine or asking about it, the most useful thing you can do is have an honest conversation about what creatine actually does (a small boost in short-burst power), what it doesn’t do (it won’t dramatically change their physique or make them a better athlete overall), and why the medical community is cautious about it during adolescence. For most young athletes, the fundamentals of training and nutrition will deliver better results with zero uncertainty about safety.