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Cassie Fien: How a supplement changed my life

10 Nov 2022

Cassie's story

How a supplement changed my life

Australian marathon runner Cassie Fien considers herself a “straighty 180”. A good person, who did everything above board. She was careful. She never imagined she’d find herself testing positive for a banned substance.

"I didn’t buy it online or down a dark alley or on the black market. I went into a physical supplement store and bought it off the shelf,” Cassie explained.

A high-intensity day job combined with intensive marathon training meant that Cassie needed a lot of energy. At the time, she didn’t feel that she could get that through food, so turned to supplements.

Wanting to make good choices, Cassie chose an all-natural product containing something called ‘Nandina Fruit Extract’. She checked the product against the Australian Anti-Doping Agency’s list of dangerous products – it wasn’t on there. She checked the ingredients against the World Anti-Doping Agency’s Prohibited List – nothing was on there.

Later, researchers from the Australian Anti-Doping Agency (which later became Sports Integrity Australia) would tell her that Nandina Fruit Extract contained the prohibited substance higenamine. Higenamine had only been added to the List four months before Cassie returned a positive test, but it didn’t matter. Even those SIA researchers, who double checked Cassie’s story, found that there was no obvious way for an athlete to find out that Nandina Fruit Extract contained a prohibited substance. That was one of the problems, Cassie felt: “Supplement companies are out to disguise what they’re doing. That’s why it reads ‘Nandina Fruit Extract’ on the label, and not ‘higenamine’.”

Because she could prove she had gone to every possible length to be clean, Cassie’s ban was reduced to nine months. But the emotional toll of testing positive and being banned for doping at the height of her career changed Cassie’s life, forever ending her drive to compete at an elite level.

Cassie now supports a food first approach to nutrition, although acknowledges how difficult that can be. “How is it possible?” she asks, “Energy drinks, energy gels, even Red Bull – they're all supplements.”

She challenges athletes who are considering taking a supplement to take care.

"For things like iron or calcium, go to a doctor, make sure you actually need it. Get advice from a registered dietitian. Put a reminder in your calendar of the date the WADA Prohibited List comes out and check anything you’re taking. Check every single year.”


'Cassie Fien: How a contaminated supplement changed my life' | Presented by Cassie Fien, marathon athlete

Content presented live at the 2022 Cambridge Athlete Forum. See also:


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