As Amazon continues its push into health care, the company has bolstered its health and wellness offerings, but a recent customer story showcases the difficulties Amazon faces in the "largely unregulated" supplement market—and the potential risks for consumers, Louise Matsakis reports for WIRED.

Cheat sheets: Evidence-based medicine 101

Amazon for years has been selling health and wellness products, but there's been growing concern in the industry at large over "fake" supplements making their way into the marketplace. Last year, a study concluded that many supplements marketed for muscle growth, sexual enhancement, and weight loss contain unapproved or recalled pharmaceuticals that have "the potential to cause serious adverse health effects."

Amazon's supplement problem

Last week, during Amazon's Prime Day sales, the fake supplement problem was on full display for Amazon. Matsakis reports that a customer, Anne Marie Bressler, received an email from Amazon, warning that the probiotics she’d purchased were likely fake.

In the automated email to customers, Amazon wrote, "If you still have this product, we recommend that you stop using it immediately and dispose of the item." Amazon told customers they would receive a full refund.

According to Matsakis, the company discovered that an Amazon merchant sold a knockoff version of probiotics made by Align, a Procter & Gamble (P&G) brand. Amazon did not disclose how many customers purchased the fake supplements, but those who did purchase the supplements received the email Matsakis reports.

Mollie Wheeler, a spokesperson for P&G, said the company is aware that a counterfeit version of their product was sold online. Wheeler added that Amazon "confirmed they have stopped third party sales of the Align products in question and … is only selling Align product received directly from P&G manufacturing facilities."

Amazon's next steps

An Amazon spokes­person in a statement told USA Today that the company "strictly prohibits the sale of counterfeit products. We invest heavily in prevention, take proactive steps to drive counterfeits to zero, and work with and empower brands through programs like Brand Registry, Transparency and Project Zero."

The spokesperson added that company investigates "every claim of potential counterfeit thoroughly, and often in partnership with brands," adding,  "[A]nd in the rare instance where a bad actor gets through, we take swift action, including removing the item for sale, permanently banning bad actors, pursuing legal action, and working with law enforcement when appropriate."

What is Amazon's legal responsibility to consumers?

However, Amazon did not respond to a question about whether it plans to test the counterfeit supplements' for potentially harmful ingredients, which can leave patients who purchased and used the products unsure if their health is at risk, Matsakis reports.

And consumers who purchase supplements from Amazon that result in harm currently have few legal options, Matsakis reports. In the past, courts have ruled that third-party marketplaces like Amazon and E-bay are not responsible for products offered by its third-party vendors, even if those products have been recalled, Matsakis writes.

But Amazon is both a third-party marketplace and a retailer, and retailers can be held directly responsible for selling counterfeit supplements, according to Matsakis. Earlier this month, for instance, the U.S. 3rd Circuit Court of Appeals ruled that Amazon is liable for some harmful products sold by third-party sellers because Amazon's system enables vendors to "conceal themselves from the customer, leaving customers injured by defective products with no direct recourse." However, Eric Goldman, a professor at Santa Clara University School of Law, notes that the ruling did not set a new precedent and Amazon has asked the court to review its decision (Matsakis, Wired, 7/19; Baig, USA Today, 7/22).