Mediterranean diet linked to reduced brain shrinkage in old age
A new study led by researchers in Scotland has found that older people who ate a Mediterranean-type diet went on to experience less brain shrinkage than those who ate other types of food. The research is published online on Wednesday 4 January in the journal Neurology.
A person's brain begins to reduce in size from early adulthood as we naturally start to lose nerve cells and the connections between them. This shrinking accelerates as people reach old age and can result in some increased difficulty with certain aspects of memory and thinking. This natural loss of nerve cells is different to the much quicker, more severe brain-shrinkage that is caused by diseases like Alzheimer's.
The researchers in this study looked at the eating habits of 967 people without dementia, who are members of the 1936 Lothian Birth Cohort. This group of people –all born in 1936 – took part in a mental ability test at the age of 11 and have participated in a variety of studies throughout their lives, allowing researchers to look at how intelligence and lifestyle factors affect health as we age.
Of this group, 401 volunteers had MRI scans roughly three years apart; the first at around age 73 and the second at around 76. The researchers found that people who had earlier reported having more of a Mediterranean-type diet experienced less brain shrinkage between the two scans than those who had adopted a less Mediterranean-type diet. A Mediterranean diet was assessed as being one high in vegetables, legumes, cereal, and fish while low in meat and dairy products.
Dr David Reynolds, Chief Scientific Officer at Alzheimer's Research UK, said:
"A Mediterranean-style diet that is low in meat and dairy but rich in fresh fruit and vegetables, cereals, beans, nuts and 'healthy' fats like olive oil, has been linked to a range of health benefits. This study adds to previous research highlighting the importance of this kind of well-balanced diet in maintaining a healthy brain as we age. While the study points to diet having a small effect on changes in brain size, it didn't look at the effect on risk of dementia. We would need to see follow-up studies in order to investigate any potential protective effects against problems with memory and thinking.
"The brain, just like other parts of the body, can be affected by the way we live our lives. While a balanced diet is one way we can help to maintain a healthy brain, the best current evidence points to a number of other lifestyle factors that can also play a role. These include not smoking, staying mentally and physically active, only drinking in moderation and keeping blood pressure and cholesterol in check."