The two foods are rich in phosphatidylcholines, compounds that help maintain brain health, and people who regularly eat them are 28 per cent less likely to suffer from dementia, researchers from the University of East Finland estimate.
They tracked the diets and health of 2,500 men, who were aged between 42 and 60 at the start of the study, for 22 years, during which time 337 of them developed dementia.
They found a correlation between the amount of eggs and meat the men ate and the risk of dementia; in other words, the more they ate, the lower the risk. The findings are "significant", the researchers say, as dementia has become so prevalent, affecting more than 50 million people around the world.
Choline is an essential nutrient that's needed to make acetylcholine, a neurotransmitter. The latest findings echo those of earlier studies that have found that choline plays a key role in preventing cognitive decline.