WASHINGTON -- Walking into a Smoothie King, it's hard not to notice shelves filled with protein powders, muscle builders, creatine and supplements. Even the smoothies are packed with extra protein, like the popular Gladiator, boasting 45 grams in a serving.

"We want to give a little bit of protein in all the smoothies," said Ashburn, Va., store owner Brad Lepp. "Everyone knows you need a little bit of protein in your body and in your diet."

In the three years that Lepp has owned his store, he said, sales of those products continue to increase, especially among teens. Those are kids like 17-year-old Max Heller.

"With hockey, I was having trouble gaining weight a little, so I just wanted to put some more weight on," Heller said.

Heller plays center on Churchill High School's hockey team. He started drinking whey protein shakes for breakfast and after working out. It helped him gain the weight and muscle he needed to be competitive on the ice.

"It wasn't like I was eating a lot of Burger King and McDonald's and gaining weight and gaining fat," Heller said. "I definitely saw a lot of muscular gain and I was getting stronger."

Children's National Medical Center Orthopedic Surgeon Dr. Jeffrey Hanway works with child and teen athletes. He said this sports culture of bigger is better may be influencing teen athletes to use muscle enhancers like whey protein powders and creatine.

"There is a mindset when you're trying to get bigger, faster, stronger that can certainly lead to problems," Hanway said.

Whey is a type of protein made from cow's milk. It's said to help build and repair muscle after a workout. In moderation, it's safe.

"Adding a little protein to a shake once a day is fine, but drinking three protein shakes a day is giving you protein you don't need and could give you problems," Hanway said.

The more controversial creatine is a protein-like compound produced naturally by the liver and kidneys. It helps release energy in the muscles, giving athletes short bursts of energy that are good for lifting weights or sprinting. Side effects include muscle cramping and nausea.

Overuse of those types of enhancers can be dangerous, creating problems like kidney stones, severe dehydration and organ failure.

One Virginia man blogged about his experience with creatine, which resulted in kidney stones. He wrote of the extreme pain and severe dehydration.

Experts recommend parents keep a watchful eye on athletes who are taking enhancers. They need to make sure kids are drinking enough water and not taking too much of any supplement.

Heller said his parents checked out the whey protein before he started using it and keeping hydrated has always been a priority.

"I always make an extra effort to drink a lot of water. Anyone who's an active athlete should," Heller said.

More Information:

Mayo Clinic Information: Creatine

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