When Ngarrindjeri great-grandmother Maxine Risk-Sumner was diagnosed with type 2 diabetes in 2008, she began a journey that saw her lose 45 kilograms and turn her life around.

Ms Risk-Sumner told 891 ABC Adelaide's Mornings program she learned she was sick after being hospitalised with a "mystery" illness.

"The doctor soon discovered my blood sugar was high and he said to me, 'did you know you were diabetic?'," she said.

Ms Risk-Sumner was referred to her GP who confirmed she had type 2 diabetes.

When she asked her doctor how she could get rid of it, he replied, "your people find it very hard".

"When somebody categorises me and diagnoses me not as a patient but as an Aboriginal — because I am black — that makes me more determined to override what [was] said," Ms Risk-Sumner said.

Her doctor prescribed medication and referred her to a diabetic educator and nutritionist.

"I thought, 'how can these people help me? All of my family has type 2 diabetes'," she said.

Over the next 12 months, Ms Risk-Sumner learnt how she could change her lifestyle to better her health.

She described the experience as "absolutely amazing".

Food as addictive as alcohol, drugs

Ms Risk-Sumner said at the time of her diagnosis she was obese.

"I reckon I wore size 20 clothes," she said.

"Now I wear [size] nine kid's jeans."

With the help of her diabetes educator, Ms Risk-Sumner changed her whole perception of food and what she had been eating.

"Food is just as addictive as alcohol and drugs," she said.

She removed manufactured and processed foods from her diet and began eating only fresh, natural foods.

"I can't believe how big I was and how small I am now," she said.

By combining her change in diet with physical activity, Ms Risk-Sumner lost 45 kilograms over five years.

Access issues for Indigenous communities

Professor Alex Brown, deputy director and program leader of Aboriginal research at the South Australian Health and Medical Research Institute (SAHMRI), said Ms Risk-Sumner was a perfect example of how change could happen with hard work.

"Aggressive approaches to intensive lifestyle and dietary change, and the right medical care and education, can really make a difference," he said.

Maxine Risk-Sumner (centre) with staff members of the Gunditjmara Aboriginal Cooperative Health Clinic in 2010. ( Supplied: SAHMRI )

Professor Brown said remote Indigenous communities faced the difficulty of scarce supplies of fresh foods.

"People with the least [wealth] and least access to healthy food pay the most for the very things that we encourage them to consume," he said.

"We have this triple whammy of poverty, high-risk [of diabetes] and trouble accessing what you need."

Ms Risk-Sumner said she had noticed within her own community that others had begun to take more notice and care with what they were eating since witnessing her results.

She also now carries five-kilogram hand weights every time she goes for a walk and said she had become addicted to exercise.

"Weights are my lifesaver because muscle is the only thing that will burn the bad fats in your body," she said.

"As a grandmother, I've got muscles."