Woman who eat well in middle age are more likely to be healthy in their 70s, according to a new study carried out in the US.
Researchers at the Harvard School of Public Health and the Brigham and Woman's Hospital in Boston, Massachusetts examined the diets of 10,670 women.
Each was asked to complete a questionnaire in their late 50s and early 60s before their health was assessed 15 years later.
Some 11 per cent of the volunteers were deemed to be "healthy agers" as they were free from cognitive conditions such as dementia and other chronic ailments.
The rest of the group were classified as "usual" agers", meaning they had suffered with at least one health issue.
The study, which was published in the Annals of Internal Medicine journal, found that those who consumed a healthy diet in middle age were more likely to be in the smaller group.
A healthy diet is considered to be on which includes a high intake of fruit, vegetables and whole grains.
Dr Simon Ridley, head of research at Alzheimer's Research UK, said studies such as this help to highlight factors which can make a person's risk to health problems in old age greater.
"Diseases like Alzheimer’s are likely to be caused by a complex mix of genetics and environmental factors, and investment in research to understand these factors is vital for finding preventions," he added.
"Although there’s currently no certain way to prevent dementia, the best evidence suggests people can lower their risk by eating a healthy, balanced diet, exercising regularly, not smoking, and keeping blood pressure in check."
The study did not state what happened to the women after the age of 70.
Recent research from the University of Rochester Medical Centre in New York suggests that someone whose diet is high in copper is more likely to develop dementia.
Despite this, the Alzheimer's Society has said that people should not look to cut the mineral out of their diets as it also has health benefits.
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