She is part of the minimalist movement, where people adopt an anti-clutter, anti-consumerist and anti-materialist mindset.

She runs a blog called 365 less things, in which she aims to throw out one item a day.

"A lot of people buy a lot of stuff they don't need and put themselves in terrible debt," Mrs Madsen said. "The amount of money wasted and the strain that has on natural resources is just incredible.

"There has to be another way for the finances of the world to stay stable without producing a lot of unnecessary crap all the time."

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Mrs Madsen lived in the United States for seven years, where she "let my hair down because shopping in America is much less expensive than here".

She moved into a smaller house when she returned home and did not have enough room for her family's possessions.

"It didn't take me long to stop shopping in Australia, considering the price you have to pay for a lot of things," she said.

"My husband and I like to travel and we don't want to be tied down by possessions."

Her husband encouraged her to start the blog, which helps her inspire others to "minimise their belongings and let go of things they don't want".

People often felt tied to possessions for "reasons like guilt and obligation".

Mrs Madsen used to be envious of people with big houses.

"Now I wouldn't have a bigger house if you paid me," she said.

"It's less to heat, less to clean, less carbon footprint."

She recycles most things she discards.

Books were among the most treasured possessions that people, even minimalists, were reluctant to part with, she said.

She urged people to switch to ebooks, which she said meant less dust, less mould and fewer trees cut down.