Australians spend the equivalent of 18 days every two years in the bathroom.

No prizes for guessing that for most of it they're sitting but in the spirit of multitasking, perhaps it's also worth asking what else people do during their toilet time.

The Cancer Council at least thinks so. Its survey of more than a thousand older Australians concerning their pooing habits found a quarter take their phones with them.

Of these, nearly half (45 per cent) admit using their device to scroll social media, while four in 10 read the news.

Some 23 per cent also send and receive texts while doing their business and another 23 per cent play games.

The nation's bathroom activities are the focus of this year's bowel cancer screening campaign, with home-testing numbers disappointingly down and 50- to 74-year-olds being urged to 'Get2It'.

The Cancer Council reckons 35 minutes a day in the smallest room in the house is more than enough for those eligible to do the test sent to them free in the mail every two years and potentially save their lives.

Screening rates for the second-biggest cancer killer sit at 43.5 per cent but with a fifth of Australians insisting bathroom time is about maintaining good health, that's not good enough, says CEO Tanya Buchanan.

"Countless lives can be saved if eligible Australians, especially those in their 50s swapped out time spent scrolling on their phones while on the loo, with bowel screening time," she said.

Federal Health Minister Mark Butler says if the screening rate can be permanently raised to 60 per cent, around 84,000 lives could be saved by 2040.

"Screen time is a feature of modern life and we want screening time to come just as naturally, so why not use your next bathroom stop to complete the test or add a reminder to your calendar," he said.

Research shows placing test kits in the bathroom straight away and setting reminders on phones are worth doing.

Former NRL stars Petero Civoniceva and Geoff Toovey and commentator Andrew Voss have also been enlisted to help spread the word.

The latter says the cause is close to his and his family's heart.

"It really hits home for me because I've seen first-hand how devastating bowel cancer can be after my grandmother was diagnosed ... late in the piece before sadly passing away," Voss said.

"Early diagnosis could save your life."

Testing kits are quick and hygienic to complete at home and return in the post.