Accused Australian drug trafficker Cassie Sainsbury’s “ultimate” eight-week weight-loss diet and fitness guide is available online to anyone who wants to drop those pesky extra kilograms.

The 22-year-old and self-professed personal trainer and nutritionist’s E-book Shape Yourself in 8 Weeks, which is riddled with grammatical errors, is selling for around $60 a pop while she remains in a Colombian prison.

Ms Sainsbury has been in Bogota’s El Buen Pastor Prison since she was arrested after 5.8 kilograms of cocaine was allegedly found inside 18 headphone boxes in her suitcase at El Dorado International Airport in April.

Ms Sainsbury’s family initially claimed she was in Colombia to promote her personal training business, but later confessed through her lawyer she was attempting to smuggle drugs out of the country.

The Adelaide woman’s self-published weight loss book gives a “few words of wisdom” such as avoiding the scales because they don’t take into account “muscle weight” and not worrying about the occasional cup of tea with almond or full-cream milk.

“Don’t let people put you down, even if you don’t finish the program, don’t be sad,” Ms Sainsbury writes in the opening lines of her E-book.

“You made the first step and you tried, if you fall off the wagon, jump back on and give it your all!”

The book, published in 2015, also features photographs of the ‘wellbeing coach’ doing push-ups and crunches on the beach.

Criticising ‘fad diets’ that cripple the bank account and fail to keep the weight off long-term, Ms Sainsbury also recommends a healthy eating regime that nourishes the body.

“You need calories to keep your heart beating, mind alert, muscles working, and to give you the energy you need to get you through your day; this means no skipping meals!”

Breakfasts she suggests include yoghurt with prunes, ham and chive omelettes and porridge with two tablespoons of brown sugar.

Since entering prison, Ms Sainsbury has complained about the meals on offer to inmates, saying the “horrible food” was giving her health issues.

“I don’t eat red meat and I told the doctor I needed to see a dietitian and they just basically said, ‘oh well you have to eat what you’ve been given’,” she told News Corp.

Through her lawyer, Ms Sainsbury has admitted she attempted to smuggle cocaine into Australia, but said she did so out of fear an international drug syndicate would kill her and her family if she refused.

Her Colombian attorney Orlando Herron told Nine Network’s 60 Minutes his client had been innocently lured by an advertisement on the website Craigslist that promised a loan and a trip to London. The ad allegedly did not mention any illegal activity.

“If you don’t get to fly, we will be threatening or killing your family for you,” Mr Herron quoted the ad as saying.

The Nine Network has also reported Ms Sainsbury was a prostitute at a brothel in western Sydney.