Having an unhealthy childhood could affect the brain in later life, according to new research.
A child’s body mass index (BMI), blood pressure and physical activity levels have been linked to differences in the brain by the age of 20 – particularly the areas linked to dementia.
While it is known that a person’s health in mid-life can be a potential predictor for dementia in their later years, researchers have not previously tracked whether there could be an impact from childhood onwards.
Experts said the new study, published in the journal eBioMedicine, suggests that being unhealthy in childhood and adolescence could set the stage for later decline in brain health.
Researchers, led by a team at the University of Oxford’s Department of Psychiatry and in collaboration with University College London, examined data from 860 people who are taking part in the long-term Avon Longitudinal Study of Parents and Children.
The study is tracking people’s data over a long period of time by examining various measures linked to their health.
The academics looked at blood pressure and BMI when children were aged seven to 17, their physical activity levels when they were aged 11 to 15 and brain scans from young adulthood when they were around 20 years old.
The scientists found that markers of poorer cardiovascular health – such as higher childhood blood pressure and faster growth of BMI across teenage years – were associated with differences in the structure of a type of brain tissue called grey matter, including its thickness and surface area.
The links were particularly evident in brain regions that are known to be affected in case of dementia in old age.
Similar links between heart health and brain health have already been shown in older patients with memory difficulties and dementia, they added.
Researchers said their findings provide “preliminary evidence” that dementia risks could be identified and mitigated earlier in life.
They called for further work to look into the findings but suggested it may have implications on timings of “preventative measures”.
“Our research shows that cardiovascular health in the earliest stages of life may already be important for the structure of brain regions known to be affected in dementia in old age – much earlier than previously thought,” said lead author of the paper Holly Haines.
The co-author of the paper, Sana Suri, an associate professor from the Department of Psychiatry at the University of Oxford, added: “The findings suggest that we should be thinking about targeting modifiable lifestyle risk factors, such as obesity and exercise, decades before current lifespan models of dementia suggest.
“The early adolescent years merit greater consideration in the context of dementia prevention.”
Commenting on the paper, Dr Richard Oakley, associate director of research and innovation at the Alzheimer’s Society, said: “Dementia is the UK’s biggest killer. Although no single behaviour is guaranteed to prevent dementia, we do know there are things you can do to reduce your own risk.
“Certain factors, such as being overweight and lack of exercise between the ages of 40 to 65, are known to be linked to a higher risk of developing dementia later in life."
However, this study aimed to understand if poor cardiovascular health in childhood could increase the risk of dementia, he said.
“The study found that where being overweight, lack of exercise, and high blood pressure were present in early life, there were changes in the brain regions that could contribute to developing dementia, suggesting that it’s never too early to make healthy changes to reduce your dementia risk.”