What You Don't Know Might Kill You

Each eight-ounce Redline bottle notes that one serving is four ounces and has a warning that reads, NOT FOR USE BY INDIVIDUALS UNDER THE AGE OF 18 YEARS. But such warnings are lost on the prime consumers. As Alsop says, "We've found that young men don't read labels."

How does an idea for a supplement go from the brain of Rene Gonzalez or Jack Owoc to a mall near you?

Companies that outsource manufacturing, as Gonzalez's does, are in the vast majority, and they usually rely on the manufacturer to obtain ingredients. Those that make their own products, such as VPX, order most of their raw materials from abroad, often from Asia.

Materials from overseas arrive with a certificate of validation from the exporter. "[But] you have to treat that like just a piece of paper some guy in China wrote something on," says Patrick Arnold, who before he rose to fame as the BALCO chemist, popularized the andro supplement that was in McGwire's locker in 1998. Says Arnold, "If you are serious about quality control, you have to test everything."

Some manufacturers, like VPX, rigorously screen the raw materials they receive; others trust the suppliers, at the consumer's risk. Balanced Health Products, the manufacturer of StarCaps, said its supplement was probably contaminated by raw materials imported from Peru. "Like any business, there are companies you can trust to do the testing and those that you cannot," says Arnold.

Once the materials are in hand, a large manufacturer, like VPX, can decide what to mix together and call a supplement. Gonzalez's options, on the other hand, are more limited. Because the size of his order won't be large enough to warrant its own production run from the manufacturer, he can only commission a so-called "me-too" product, essentially a copy of an existing supplement in the marketplace that he then brands with his label.

To make a brand rise above the crowd, though, a company can't just churn out another basic creatine or whey protein. It takes a different formula, or the real jackpot: the inclusion of a novel ingredient. It is during the race to create something new, when supplement makers spend hours poring over science and nutrition journals—sometimes using themselves and their coworkers as guinea pigs for experimental formulas—that they're likely to jump the gun and embrace ingredients that have proved neither safe nor effective.

A few years ago supplement makers turned ecdysterone, an insect development hormone, into all the rage. The leap that companies made was spelled out in the ecdysterone information page at Bodybuilding.com, the leading online-only supplement purveyor: "Could there be some correlation between insects' superior strength ratio and this compound? What would the effects be on vertebrates such as mammals? If we had the proportionate strength of an ant, for example, we could easily pick up a car." A Bodybuilding.com article by a former chief of research for a major nutrition company called ecdysteroids the "Steroidal Holy Grail."

Except ecdysterone doesn't have any effect on humans. "Studies in my lab have shown that ecdysteroids are completely innocuous in mammals," says Ronald M. Evans, a professor at the Salk Institute for Biological Studies in San Diego. "Spinach, for example, is loaded with [ecdysteroids], but these molecules provide no muscle-building properties in humans."

Instances in which supplement makers have moved faster than science, or dodged it entirely, abound. For example: