Dementia may be avoidable and doctors should take a more optimistic approach to the condition, according to research involving two UNSW academics.

In an editorial published in the British Journal of Psychiatry this week, the authors challenge previous understanding of dementia.

"Emerging evidence challenges the clinical pessimism often associated with dementia and points to a variety of ways of improving impairment and reducing risk of further deterioration," said the lead author, Dr David Burke, a conjoint senior lecturer in the School of Public Health and Community Medicine, at St Vincent's Hospital.

The authors highlight recent evidence which finds that healthy brains, ageing brains and impaired brains have a remarkable capacity to generate new brain cells (neurogenesis) and new connections (neural plasticity).

They suggest that the intake of fish oil, antioxidants and vitamin B12, as well as social interaction and regular exercise, may be beneficial.

The literature shows that neurogenesis and neural plasticity may be impaired by vascular risk factors including high blood pressure, high cholesterol, smoking, diabetes, obesity, carotid stenosis, heart attack and stroke.

"Taken together, these findings open the door to an array of possible new directions in the treatment and prevention of cognitive impairment and dementia through interventions that promote mental health, lifelong education, functional intimate relationships and social engagement, and that target healthy eating, dietary supplementation, exercise and effective cardiovascular treatment (when needed)," the paper states.

"Our paper also highlights the need for advances in the neurosciences to be translated into clinical research and then clinical practice at the individual and public health levels through close association between neuroscientists and clinicians," said Associate Professor Michael Breakspear, from UNSW's School of Psychiatry and the Black Dog Institute. "It also has implications for other psychiatric disorders that may have a vascular component, such as depression."

The co-authors on the paper are Professor Ian Hickie and Dr Jurgen Gotz, both from the Brain and Mind Institute at the University of Sydney.