There are seven lifestyle habits that lower the chance of people at genetic risk of dementia developing the condition, research suggests.
Researchers say the findings are good news for those who are at the highest genetic risk of dementia.
“These healthy habits in the 'Life’s Simple 7' have been linked to a lower risk of dementia overall, but it is uncertain whether the same applies to people with a high genetic risk," said Adrienne Tin, of the University of Mississippi Medical Centre in the US.
“The good news is that even for people who are at the highest genetic risk, living by this same healthier lifestyle [they] are likely to have a lower risk of dementia.”
The seven cardiovascular and brain health factors are known as the American Heart Association’s Life’s Simple 7.
The study looked at 8,823 people of European ancestry and 2,738 people of African ancestry over 30 years.
Researchers calculated the genetic risk scores at the start of the study.
The research found that the group with the highest genetic risk included those that had at least one copy of a gene variant associated with Alzheimer’s disease.
Of those with a European background, 27.9 per cent had the gene, while 40.4 per cent of those who had African ancestry had it.
By the end of the study, 1,603 people with European ancestry developed dementia, as did 631 people with African ancestry.
Those of European background with the highest scores in the lifestyle factors had a lower risk of dementia, including some in the group with the highest genetic risk.
For each one-point increase in the lifestyle factor score, there was a 9 per cent lower risk of developing dementia, the study found.
It found that compared with the lowest score for those with European ancestry, the intermediate and high-score categories were associated with 30 per cent and 43 per cent lower risk for dementia, respectively.
Among those with African ancestry, the intermediate and high categories were associated with 6 per cent and 17 per cent lower risk.
“Dementia risk depends on many factors," said Dr Rosa Sancho, head of research at Alzheimer’s Research UK.
“Some, like our age and genetic make-up, we cannot change, while others, like diet and exercise, we can.
“This study supports the idea that what is good for the heart is also good for the brain – and that this holds true even for people with a higher genetic risk of dementia, at least for participants of European ancestry.
“Although the researchers monitored participants for all forms of dementia, when grouping people according to genetic risk they focused only on genes that increase risk of Alzheimer’s disease, just one cause of dementia.
“Also, health scores were taken at the start of the study, but what we don’t know is whether the participants’ healthy habits lasted for the duration of the study.”
Dr Sancho said that future research should include risk genes for all forms of dementia, and ideally should continually monitor health habits.
The research is published in the Neurology journal.