According to experts over 24 million people worldwide are thought to suffer from dementia, and many of these people live in low and middle-income countries.
With aging populations around the world increasing, many health systems are coming under burgeoning pressure and there has been as a result more interest in whether dietary factors, particularly oily fish and meat, might influence the onset and/or severity of dementia.
Some research has suggested that oily fish which is rich in omega-3 long-chain polyunsaturated fatty acids, are positively related to cognitive function in later life and it has also been suggested that increased meat consumption may be related to cognitive decline.
In order to examine these theories, a group of international researchers conducted a study of 14,960 people over the age of 65 in 7 middle to low-income countries.
The participants living in China, India, Cuba, the Dominican Republic, Venezuela, Mexico, and Peru provided data on their diets by way of face-to-face interviews, and dementia was diagnosed by using validated culturally and educationally fair criteria.
The researchers found that in each country except for India, there was an inverse association between fish consumption and dementia prevalence and the findings support previous conclusions from industrialized countries that increased fish consumption is associated with lower dementia prevalence in later life.
The authors suggest that this relation is not due to poor overall nutritional status in those with dementia, because meat consumption tended to be higher in this group and they say the relation between meat consumption and dementia remains unclear.
You can read the results of their study in the August 2009 issue of the American Journal of Clinical Nutrition.