Herbalife is a multi-billion-dollar multi-level marketing supplement company

that was forced to pay hundreds of millions of dollars to settle charges of deception

and corrupt business practices. It also holds the distinction of being

the dietary supplement most frequently implicated in injuring the livers of consumers.

Herbal does not mean innocuous. Cases of severe liver toxicity associated with herbal life supplements

starting to be published in 2007

around the world. As the accompanying editorial summarized, there were 22 cases of liver

damage following herbal life intake in the first two reports with two patients developing

fulminant liver failure, requiring liver transplantation, only one survived.

The editorial concluded that this clearly shifts the risk-benefit ratio against its use.

Maybe it's contaminated with chemicals or heavy metals, maybe due to contamination with

a liver-toxic bacteria found in implicated products?

Additional reports continued to be published, followed by rebuttals written by

herbal life company representatives questioning cause and effect, no small task, given that

people were taking up to 17 different herbal life products at one time. So how strong is the evidence?

A key factor to look for is re-challenge tests or positive re-exposure.

Did someone decide to take the product again after the initial liver injury resolved

and did their symptoms return on re-challenge.

Based on stringent causality assessment methods like positive re-exposure tests,

cause and effect is considered probable for at least a few herbal life products.

There's such a moving target, though, with hundreds of different products,

marketed globally in over 88 markets,

...