A Western Australian man has told how he lost his liver after taking popular weight-loss products widely available in protein powders and supplements.
Matthew Whitby was two weeks from death and needed an emergency liver transplant after taking a protein powder containing green tea extract and a supplement with garcinia cambogia — a tropical fruit used in weight-loss supplements.
Green tea extract is a concentrated form of the popular tea and is favoured for its purported weight loss properties and anti-oxidant effects.
But in some susceptible individuals, doctors say it can cause liver failure even in moderate doses, and has been reportedly linked to dozens of cases of liver failure around the world.
There have also been cases of liver damage linked to garcinia cambogia.
Mr Whitby was so close to death after taking a protein powder and supplement containing the extract that he had to accept a donated liver with Hepatitis B.
The young father will have to take a raft of medications for the rest of his life and has spoken out to warn others.
"I didn't think something you could buy online or just over the counter did the damage that it did to me,'' he said.
"They didn't say anything about 'could cause liver failure'."
Taxpayers will have to foot the estimated $150,000 bill for Mr Whitby's liver transplant, yet Australian products containing green tea extract typically contain no warnings.
And, because green tea is technically a food, it often falls into a regulatory mine field.
Products which make a therapeutic claim, like the garcinia cambogia supplement are regulated by the Therapeutic Goods Administration (TGA).
But in products such as protein powder, they are usually regulated through Food Standards Australia and New Zealand with enforcement by state health authorities.
The TGA said it was investigating the case as a part of a wider review, "the results of which will be made public if there is sufficient evidence of a safety issue to warrant further action".
Mr Whitby's doctors have said the green tea extract is the most likely culprit for his liver failure, but said as there are many ingredients in supplements and powders, it was hard to make a definitive call.
The case has been documented in the Medical Journal of Australia.
Experts said it was still safe for consumers to drink green tea in moderate amounts, with problems more likely in the tea's concentrated form.
Rising liver damage linked to herbal remedies
Mr Whitby's doctors at Sir Charles Gairdner Hospital in Perth said they were not surprised by what happened to the healthy 27-year-old.
Liver specialist Professor Gary Jeffrey works in the liver transplant centre of Western Australia and said doctors were seeing what they believe is more liver damage from herbal remedies and herbal extracts.
"We would during the year have one or two people with liver failure due to herbal remedies," he said.
"This would be the most severe form we've seen. Most of the other cases we've seen have resolved spontaneously."
While the question of warnings was up to regulators, Professor Jeffreys said he personally would like to see a product insert which listed the benefits and risks of the supplement.
"People who have normal liver function can develop liver problems with herbal extract toxicity," he said.
"There have been a number of countries around the world that have removed slimming agents from the market because of the increased rate of liver damage."
How did it happen?
The TGA said one of the products Mr Whitby consumed was a protein powder called HydroxyBurn Elite supplied by BSc.
There is nothing illegal about supplying products containing green tea extract and it is an ingredient approved for sale in Australia.
The product is no longer available on the market.
Experts think the liver failure related to green tea extract can occur because of catechins, the same element that makes it potentially beneficial, specifically a sub-group of catechins called EGCG.
"The exact mechanism of the green tea extracts on the liver isn't actually known but it can cause, at its worst, liver death," Professor Jeffrey said.
Clinical pharmacologist Professor Ric Day from St Vincent's Hospital said cases like Mr Whitby's were known as "idiosyncratic" reactions and could happen with virtually any medication.
"It is very rare and it seems like some individuals have a particular sensitivity," he said.
"So it's a lot of bad luck generally but the protection is to make sure you've got a reputable source of the drug, that you're not taking more than you should, you're following the instructions.
"A general principle is more might not be better but it might be more toxic in those that are more sensitive."
In a statement the company said it was not aware of the case and the TGA had not notified them of the adverse event.
"In the 14 years we have been producing protein powders with added herbal extracts we have not been notified of any adverse events," the statement said.
"The individual was notably taking a garcinia cambogia supplement as well, which was not our product. Based on 14 years of well tolerated use of our product range, we will not be reconsidering our use of green tea extract."
The garcinia cambogia supplement Mr Whitby took was from a site with an Australian office address in its contact details.
Garcinia cambogia is based on a tropical fruit and gained worldwide popularity after being controversially endorsed by celebrity television doctor Dr Oz.
It has been implicated in some cases of liver damage around the world, and two liver-based adverse reactions in Australia but experts said there was less evidence of its potential risk.
Steve Scarff, the Australian Self-Medication Industry Regulatory and Scientific Affairs Director, said consumer safety was "paramount" and the industry took adverse event reports seriously.
He said Australia had a world-class system for regulating complementary medicines.
"There has been a number of reviews of green tea extract and the conclusion is that it's a low-risk herbal substance," he said.
"There are processes in place to review the safety of ingredients and products."
Who is the regulator?
A spokeswoman for the TGA said the protein powder was not on its register of Therapeutic Goods and some sports supplements were regulated as foods, rather than therapeutic goods.
"The TGA is continuing to investigate the report it received relating to the BSC protein powder and liver failure as part of a larger investigation into this issue, noting that the TGA has not received any other reports of liver failure with this product," she said.
"The results will be made public if there is sufficient evidence of a safety issue to warrant further action."