A new study has revealed that Indian people are unlikely to benefit from fish which is known to influence the onset and severity of dementia.
Oily fish are rich in omega-3 fatty acids and have been positively related to cognitive function in later life.
An international team of researchers studied 14,960 participants, aged 65 and less, living in China, India, Cuba, the Dominican Republic, Venezuela, Mexico, and Peru.
They found that each country, except India, showed an inverse association between fish consumption and dementia prevalence.
Another study had recently shown that people who live alone in middle age face nearly double the risk of developing dementia in later life compared with married or cohabiting counterparts.
The study suggested that having a partner offers protection against mental decline in later life.
The researchers also found that people who live alone in middle age and are widowed or divorced are three times more likely to develop dementia, as are people who are single at middle-aged but also when they are older.
However, women overall had less chance of dementia than men, but they called for more research on differences between the sexes.