Omega-3
levels affect whether B vitamins can slow brain’s decline
Oxford
University
While
research has already established that B vitamin supplements can help slow
mental decline in older people with memory problems, an international team have
now found that having higher levels of Omega-3 fatty acids in your body could
boost the B vitamins' effect.
The team, from the Universities of Cape Town,
Oslo, Oxford and the UAE, studied more than 250 people with mild cognitive
impairment (MCI) in Oxford. MCI is when brain function is below what is
normally expected for a person’s age but is not significant enough to interfere
with daily life.
While it is not as serious as dementia, if untreated it often
progresses to become dementia.
Dr Celeste de Jager said: 'We
previously found that B vitamins are able to slow or prevent the atrophy of the
brain and memory decline in people with MCI.
This was most effective in those
who had above average blood levels of homocysteine, a factor related to B
vitamin status that may be toxic to the brain.
Scientists in our team
initially found that there was a link between Omega-3 levels, homocysteine, and
brain atrophy rates. We wanted to find out whether Omega-3 and B vitamins might
interact to prevent cognitive decline.'
The participants were split
into two randomly-selected groups, who received either a B-vitamin supplement
or a placebo pill over two years. Their cognitive performance was also measured
and the results compared with the baseline results from the start of the study.
Dr Abderrahim Oulhaj said: 'We
found that for people with low levels of Omega-3, the vitamin supplements had
little to no effect. But for those with high baseline Omega-3 levels, the B
vitamins were very effective in preventing cognitive decline compared to the
placebo. This result complements our previous finding that B vitamins slow the
rate of brain atrophy in MCI only in those with a good Omega-3 level to start
with.'
The team also found that levels
of DHA might be more important than levels of EPA, although they caution that
more research must be done to establish whether this is true.
Professor David Smith said:
'The next stage will be to see whether providing a combination of B vitamins
and Omega-3 supplements can slow the conversion from MCI to Alzheimer's
disease. This would be an important step in the prevention of Alzheimer's
disease. We have high hopes that this trial would work but funding is not easy
to obtain for such studies.'
Dr Doug Brown, Director of
Research and Development at Alzheimer's Society said: 'These results help us to
tease apart who could benefit from taking B vitamins, suggesting that they
might only improve cognition in people who have high levels of Omega-3 oils in
their blood.
Encouragingly, these findings suggest that for some older people a
combination of fish oil supplements and B vitamins may help to improve thinking
and memory.
'As this study shows, the
relationship between nutrition and brain health is complex and we need to see
increased research efforts to help us understand the role that diet and
nutrition can play in reducing a person’s risk of dementia.'
The paper, Omega-3 fatty acid status enhances the prevention of cognitive decline
by B vitamins in Mild Cognitive Impairment, is published in the Journal of
Alzheimer’s Disease (doi:10.3233/JAD-150777).
The Oxford
Project to Investigate Memory and Ageing – OPTIMA –
has a mission to advance our understanding of the causes, treatment and
prevention of dementia in the context of providing support and education for
research participants and carers. It recruited its first participants in 1988
and over time has collected a wealth of information and samples that can be
used by dementia researchers.
