Defying guidelines from the American Academy of Pediatrics and American College of Sports Medicine, health food stores are recommending a sports supplement to underage customers.

In a study published in the latest issue of Pediatrics, researchers say they discovered that more than two-thirds of the health food stores visited by a researcher posing as a 15-year-old football player recommended creatine.

Researchers added that nearly three-quarters of sales attendants said 15-year-olds would be able to purchase creatine supplements on their own, even though most supplements contain warnings against underage usage.

Based on their findings, researchers are calling on parents, pediatricians, and educators to discourage teenagers from using creatine and testosterone boosters.

They also suggest a possible ban on selling these supplements to underage customers.

“Creatine is a natural substance that’s made by your body, and it does help the muscles with energy and muscle-producing activities,” Dr. Ruth Milanaik, the study’s senior author, told Healthline. “One of the problems is that people are under the impression that if you take more creatine, this will make your muscles get bigger, quicker. And although this is true, the truth is that you are really just stretching your muscles beyond what they are naturally ready to do.”

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Adverse effects on young bodies

Milanaik says creatine supplements can add further stress on growing bodies.

“Their muscles are already being stretched on bones that are growing,” she said. “Their ligaments are already being stretched. And their muscles are naturally growing at a much faster rate because they are teenagers. So when you’re looking at a teen’s growing body, the question is whether or not stretching the muscles beyond how they’re already growing is a good idea.”

Another concern expressed by researchers is the lack of guidance and education offered by many of the health food stores contacted in the study.

“It’s troubling that if I call a health food store, which is supposedly trying to keep me healthy, and I ask, ‘Hey, how can I get bigger?’ the answer isn’t, ‘Listen, you’re a 15-year-old kid, come on in, we’ll talk about diet and nutrition.’ It’s the offering of a product that’s specifically labeled, ‘Not for anyone under the age of 18,’” said Milanaik, who works in the Division of Developmental and Behavioral Pediatrics at the Steven and Alexandra Cohen Children’s Medical Center in New York.

This education gap becomes even more exposed when teenagers decide on appropriate dosage.

“Are you really trusting a teenager to sit down and read the label and the package insert and read how they’re supposed to use these?” asked Milanaik. “The truth is that when we put out our study, we found that 78 percent of children who were taking creatine didn’t know what dose they were taking, didn’t know what dose they should be taking, or had purposely read the label and are now taking more than what the label says, on the thought process that if a little is going to get you bigger, faster, then a lot will get you a lot larger, faster. So they’re making typical teenage adolescent decisions, but with substances that could be potentially harmful.”

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Operating in a gray area

Many supplement manufacturers put labels on their products warning against their use by children.

But, unlike warnings printed on cigarette packages or drugs, there are no laws compelling manufacturers to put warnings on supplements.

The American Academy of Pediatrics and the American College of Sport Medicine have both recommended that children not use creatine, but the Food and Drug Administration (FDA) has issued no such recommendation or regulation.

“The FDA does not regulate the supplement industry,” Milanaik told Healthline. “So really, it’s a wonderment what’s in these supplements. You cannot be 100 percent sure what’s in the supplements. You cannot be 100 percent sure of the quality of the supplements. And you cannot be 100 percent sure of the widespread side effects to the supplement because the FDA does not regulate these substances.”

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Education, regulations recommended

“I would love to see the FDA take a much closer look at the supplement industry and begin to regulate these products more closely because this is an industry that would benefit from being watched,” said Milanaik.

Researchers are also calling for increased education and awareness on the risks that supplements can pose to growing bodies.

In the absence of FDA guidelines to govern the supplement industry, Milanaik says she’d like to see manufacturers put larger, more noticeable warning labels on their products.

Finally, says Milanaik, health food stores need to shift their focus toward education, rather than just sales.

“Health food stores can make a very big difference. They can say, ‘Listen, there’s no magic pill. You’re not going to get bigger, stronger, faster with a magic pill. What’s going to help you is if you are able to diet and exercise and get sleep and live a healthy life,’” said Milanaik. “I’d rather see health food stores reinforce healthy behaviors and reading pamphlets on other types of products that are not specifically marked with an age restriction warning label, that can help kids understand that having a healthy body is about a mindset and a way of living — not a shortcut pill.”