If a celebrity endorsement seems a bit far fetched or too good to be true, it's probably a scam.
The number of Australians ripped off by product scams purporting to be endorsed by celebrities has soared by 400 per cent in the past year.
The consumer watchdog ScamWatch website has received almost 200 reports of fake celebrity-backed products in 2018, with losses totalling $142,000.
Almost two-thirds of Australians duped were aged over 45, with women more likely than men to be sucked in.
Most people lost between $100 and $500, with one victim swindled out of more than $50,000.
Images of television presenters including Lisa Wilkinson, Sonia Kruger, Georgie Gardner, Jessica Rowe, Steve Baxter and Deborah Knight have all been used in recent celebrity endorsement scams.
So too have actors Cate Blanchett, Nicole Kidman and Sally Field, along with international stars Oprah, Dr Oz, Mark Shuttleworth and Mikhail Varshavski.
One common scam works by people punching in their credit card details to sign up for a free product trial, before being stung by ridiculous terms and conditions and sneaky subscription renewals.
Delia Rickard from the Australian Competition and Consumer Commission says the groups behind celebrity endorsement scams are organised and sophisticated fraudsters.
"It's easy for them to create fake ads and websites to give credibility to their con, so people need to be very careful and sceptical about ads they read on social media and websites," Ms Rickard said.
The ACCC wants Google, Facebook and Instagram to crack down harder on fake ads.
"Most of the reports to ScamWatch involve these scam advertisements running on Google ad banners or as ads in Facebook news feeds," Ms Rickard said.
"These tech giants must do more to quickly suspend ads, as every time consumers click on a scam ad they are at risk of losing money."
Australians sprung by scams are being urged to call their banks immediately to try and arrange a chargeback, and to stop any more debits from their cards.