Matthew Whitby wanted to get fit. It almost cost him his life.

Like many young men, Matthew Whitby started working out to get fit and gain strength.

He never thought it could cost him his life.

But within three months, the young father would be in intensive care in a Perth hospital with doctors telling him he had two weeks to live.

Doctors said the most likely culprits were a protein powder containing green tea extract linked to liver failure in certain people and possibly a diet supplement containing garcinia cambogia.

With his liver failing fast, the Geraldton man’s only choice was to accept a liver transplant from a man who had hepatitis B.

“I didn’t think green tea could cause that to a liver,” he said.

“To get so close to death to being here now being able to raise my two daughters. It’s changed the way that I look at life.

“I didn’t think something you could buy online or just over the counter did the damage that it did to me. They didn’t say anything about ‘could cause liver failure’.”

Since the operation, Mr Whitby has had to return to hospital after his donated liver herniated.

He will have to take hepatitis B medication and anti-rejection drugs for the rest of his life.

It has been more than a year and only now is he about to return to work, most likely on light duties.

“It was only about a month ago I could start picking up my daughter,” he said. “That’s pretty hard.”

“I can’t just go grab a beer with a mate because they don’t recommend you drink with a transplant.

“I look back all the time and think, where would I be now if I didn’t take the product.”

Authorities have long warned about the dangers of buying supplements from overseas.

But when Mr Whitby could not find what he wanted in local shops, he thought buying supplements online from a Melbourne-based site would be safe.

He researched the products online and asked friends for advice.

He ended up buying a protein powder containing green tea extract produced by an Australian company and sold on an Australian website.

The garcinia cambogia supplement was from a website with an Australian postal address which claimed to have TGA approvals.

However experts suggest for susceptible individuals, the actual makers of the green tea extract is unlikely to matter.

He took half-doses at first, and with food, to be safe.

When he drank the shakes he got a fever, but it passed soon after.

“After about two-and-a-half weeks, I stopped taking it,” he said.

“That’s when I got weakness, fatigue … a month or two after I got the jaundice, yellow eyes and skin.

“I just felt weak. Just everyday activities were getting pretty hard. I just wasn’t getting through the day without a nap and stuff and I knew something was pretty wrong at that point.”

By Christmas Day 2014, Mr Whitby was so unwell his wife and mother forced him to go to hospital.

“They said I only had two weeks left to live and they would put me on a high priority for a transplant.

“It really didn’t click in until I woke up and then I realised with all these cords on me in ICU how severe it was.”

Mr Whitby’s health crisis could not have come at a worse time.

His partner Kiara Slater had just given birth and was trying to care for their two young daughters.

“It was really, really scary especially because we didn’t know what was wrong with him,” she said.

“It was really shocking when we found out what it was from. Even when we tell people know they’re like ‘how can that happen’.”

Mr Whitby’s case was written up in the Medical Journal of Australia, but he has spoken out publicly to warn others.

“Just be more aware,” he said. “Do a bit of research. Don’t just do what everyone’s else is doing.”

“Find out what’s in the products. See a doctor first and ask if that supplement would be okay to take.”