Vision loss and high cholesterol have been added to list of preventable risk factors for dementia.
The Lancet Commission on dementia prevention has identified 14 risk factors for dementia. They are behaviours and lifestyle factors that can come in to play even in early childhood.
The list previously including things like smoking, traumatic brain injury, and lower education levels. Now vision loss and high cholesterol have been added.
"The potential to prevent and better manage dementia is high if action to tackle these risk factors begins in childhood and continues throughout life, even in individuals with high genetic risk for dementia." the research published in The Lancet found.
"The new report estimates that the risk factors associated with the greatest proportion of people developing dementia in the global population are hearing impairment and high LDL cholesterol (7 percent each), along with less education in early life and social isolation in later life (5 percent each)."
Fourteen new risk factors for dementia identified
Auckland University neurologist Dr Helen Murray told Morning Report the research suggested up to half of dementia cases could be avoided or delayed by tackling the risk factors.
"I think what we should take it is cumulatively there's a lot of different things that we can do in our lives to try and reduce our risk of dementia in later life."
Murray was particularly interested in the link between repeated head injuries and an increased risk of dementia.
She looked at changes that could be made in the way sports were played, such as shorter seasons or not starting contact sports until 15-years-old.
"Things like that can reduce our overall lifetime risk to head injuries."
It was also important to remember that playing sport was good for overall general health, Murray said.
"Sport overall has a lot of benefits to our health so we're not advocating stopping sport entirely, but how can we play it more safely to reduce those head injuries."