A key vitamin found in meat, fish and milk may help protect the brain as it ages, researchers said.
Vitamin B12 could help stop the brain shrinking - possibly preventing memory loss in older people and dementia.
A study of 107 people aged 61 to 87 found that those with lower vitamin B12 levels in their blood were six times more likely to experience brain shrinkage compared with those who had higher levels of the vitamin.
Anna Vogiatzoglou, from the department of physiology, anatomy and genetics at Oxford University, which led the study, said: "Many factors that affect brain health are thought to be out of our control, but this study suggests that simply adjusting our diets to consume more vitamin B12 through eating meat, fish, fortified cereals or milk may be something we can easily adjust to prevent brain shrinkage and so perhaps save our memory.
"Research shows that vitamin B12 deficiency is a public health problem, especially among the elderly, so more vitamin B12 intake could help reverse this problem." She said more research was needed into whether taking a B12 supplement would result in less shrinkage.
In the study, published in the journal Neurology, brain volume loss was measured every year for five years. None of the people enrolled in the study were suffering memory loss at the start of the study and none had a vitamin B12 deficiency. The participants were given yearly physical examinations, MRI scans of their brains, tests to check their cognitive and memory skills, and blood tests to determine their levels of vitamin B12.
The results showed that the decrease in brain volume was greater among those with lower vitamin B12 levels. The authors concluded: "Low vitamin B12 status should be further investigated as a modifiable cause of brain atrophy and of likely subsequent cognitive impairment in the elderly."
Source - Independent