Last year, a woman in London made headlines after getting herself out of debt by selling her dirty underwear on the Internet for $60,000. Creepy but true. If only her customer base had known that their desires might be satisfied at a local chain store. It turns out far too many retail companies are restocking returned, used undergarments (BTW that’s illegal), and unsuspecting customers are buying them.

“The Dr. Oz Show” launched an investigation into this retail misstep (watch it at www.DoctorOz.com). Staffers purchased 11 pairs of underwear from top chain stores and sent the items out to a lab for testing. All but one tested positive for coliform bacteria, which exist in the digestive tracts of humans and are found in their waste. The good news is that most coliform bacteria don’t cause disease, but they do come from the same source as certain potentially pathogenic organisms. Half the samples also contained trace amounts of yeast. All but two samples were soiled with mold, which might indicate that the garments were kept in a damp factory or storage facility.

Fortunately, there haven’t been any reported cases of illness caused by wearing contaminated underwear, but chances are you wouldn’t associate diarrhea or another related GI disease with such a possible cause.

So, let’s just assume you should wash all garments before wearing, even those in sealed plastic packaging. For hand-wash-only undergarments, add distilled vinegar to hot water and soak them before using soap. This will disinfect like bleach, without ruining them.

Mehmet Oz, M.D., is host of “The Dr. Oz Show,” and Mike Roizen, M.D., is chief wellness officer and chairman of Wellness Institute at Cleveland Clinic.