Almost half of Scots responding to a survey have not taken any steps to keep their brain healthy.
An Ipsos Mori poll of 1000 people, aged 20 to 49, found 43% are not following simple advice, which could protect them from dementia. Meanwhile, 15% do not know if they have been doing so.
Brain Health Scotland, which commissioned the survey, said socialising, getting fresh air and keeping blood pressure under control can prevent serious illnesses.
The poll found almost a quarter of respondents – 23% – were unable to identify any protective steps which could be taken.
Brain Health Scotland is a research, education and prevention programme, which launched on Monday with initial £1m in funding from the Scottish Government.
It aims to increase the numbers of Scots making lifestyle choices to protect their brains as they grow older.
Brain Health Scotland’s director, Professor Craig Ritchie, said a lack of understanding about prevention may be partly fuelling a hidden rise in cases of dementia, Alzheimer’s disease and similar conditions.
Mr Ritchie said: “This isn’t all about doing crosswords or puzzles or sudoku in your late 50s. Good brain health could and should start much earlier than that.
“We want young people to understand that a healthy diet, socialising with friends and even getting fresh air can help protect the brain as we age.”
The project is being supported by national charity Alzheimer Scotland, whose chief executive Henry Simmons said: “The work carried out in this project could be vital in terms of our approach in the years ahead.
“We are confident it will make a lasting difference to the future of dementia care and research.”