Research commissioned by Alzheimer's Australia Vic shows there are 96,789 Victorians living with dementia. Three years ago there were 82,000 Victorians with dementia.

The research indicates this number is predicted to rise to 386,397 by 2050 if there is not a big medical breakthrough.

Local government areas with the highest prevalence of dementia are Greater Geelong, Mornington Peninsula, Monash, Whitehorse and Boroondara.

State electoral districts with the highest prevalence are Bendigo East, Nepean, Shepparton, Box Hill and Mornington.

There are more females than males living with dementia and there are 3495 Victorians under the age of 65 with the illness.

Dementia is the term used to describe the symptoms of a large group of illnesses that cause a progressive decline in a person's functioning. It is a broad term used to describe a loss of memory, intellect, rationality, social skills and physical functioning.

Alzheimer's is one of the most common forms of dementia.

"Dementia is an overarching condition and there are about 100 different types of dementia like there are many different types of cancer," Maree McCabe, chief executive of Alzheimer's Australia Vic said.

Ms McCabe said the prevalence rate of dementia per head of population is increasing.

"Dementia is not a normal part of ageing, but is more common as we age, so we have more older people in our community so there are more people who are developing dementia," she said.

And she said it is not just older Victorians living with dementia.

She said one in 13 people under the age of 65 have "younger onset dementia – in their thirties, forties or fifties" and there needed to be greater awareness of the condition.

Ms McCabe said keeping active physically and mentally can reduce the chances of having dementia.

"We do know what contributes to the different types of dementia are lifestyle factors ... exercise and remaining socially engaged and keeping the brain active help," she said.

Ms McCabe wants a public awareness campaign for dementia.

"There is going to be nobody in Australia, or Victoria for that matter, who will not be impacted at some stage by dementia," she said.

"As a community we need to be able to support people living with dementia in a much more effective way – right now there is a massive stigma and we want to disrupt that stigma and educate people and let them know how they can better support their loved one," she said.

Dementia was a leading cause of death in Australia – "most people don't know that".

The research was commissioned by Alzheimer's Australia Vic and carried out by NATSEM and University of Canberra.