SYDNEY (AFP) - An Australian blogger who lied about having brain cancer and claimed to have cured herself with natural therapies has been ordered to pay A$30,000 (S$31,663) in legal costs.

Belle Gibson, 25, launched a popular cookbook and smartphone app in 2013 on the back of assertions she had overcome the disease through alternative remedies such as Ayurvedic medicine and a diet free of gluten and refined sugar.

But in 2015 she admitted to an Australian magazine that she had made up the diagnosis.

The Federal Court, which found her guilty of misleading the public last month, said she had 60 days to pay A$30,000 in legal costs incurred by Consumer Affairs Victoria, which brought the case, or face possible jail time.

She could also face penalties of up to A$220,000 in fines and her company up to A$1.1 million, with the court setting a later date to hand down its decision.

Gibson was also barred from "representing that she had been diagnosed with brain cancer" before the case started in May last year, Justice Debra Mortimer wrote in her judgement.

The judgement added that Gibson's company made some A$420,000 from the cookbook and app, and that a pledge to donate most of the earnings to charities or good causes was not met.

Mortimer said last month "Gibson deliberately played on the genuine desire of members of the Australian community to help those less fortunate".

"The Whole Pantry" cookbook had 80 mostly plant-based recipes that drew inspiration from Gibson's purported battle against cancer.

Gibson's lie began unravelling when it emerged in early 2015 that she had failed to donate profits from the sales of her cookbook to charity as promised and friends started to question her diagnosis via the media.