Writing about omega 3 fatty acids and fish oil is something I seem to do very often! These fats are essential for the health of our bodies and I feel they deserve my continued concentration! Today I would like to bring your attention to two recent studies (1,2) which were carried out in older adults (aged 65 or over). Both studies highlight the potential health benefits of oily fish and their constituent omega 3 fatty acids.
The first study was interesting since it looked at individuals who were already quite unwell. The scientists wanted to see if there was any relationship between omega 3 fatty acids and mortality. The study involved 254 elderly patients admitted to St Olavs Hospital in Norway. The blood plasma levels of EPA (eicosapentaenoic acid), a long chain omega 3 fatty acid found in oily fish, were measured. These levels are a good indicator of dietary intakes of this fat. Mortality rate was evaluated after 3 years of follow up. The mortality rates of those patients with the lowest EPA levels was significantly higher than those with the highest levels. The authors also found that around 25% of the population had very low EPA concentrations indicating minimal dietary intakes. The indivuduals used in this study were unwell and already elderly, but the results indicate that additional EPA may have been useful in those who had low levels. The results only show an association and not cause, however it certainly implies that omega 3 are very important, even when already unwell.
For me the take home message is more to do with prevention against disease and maintenance of wellness throughout life. Keeping good omega 3 levels in the body throughout a lifetime could prevent later illness or health problems.
The second study involved over 2000 individuals aged 65 or over. They underwent a brain MRI scan at the start of the study and then again five years later. The research scientists wanted to look at something called ‘silent brain infarcts’. These are small lesions/abnormalities, caused by insufficient blood supply, in the brain that can raise a person’s long-term risk of stroke, dementia or loss of thinking skills. The participants were also given detailed questionnaires to assess their diet habits. The results found that silent brain infarcts were lowest among the participants who ate the most fish, especially oily fish, three or more times per week. The association was not seen in those eating fried fish. The study cannot prove that it was the omega 3 fatty acids that were responsible for the brain benefits, but it is likely, from previous evidence and studies, that they do play a key role. When the researchers estimated study participants’ intake of two major omega-3 fatty acids, EPA and DHA, they found a link between higher intake and lower risk of silent brain infarcts. In addition, the researchers note, the lack of a protective effect from fried fish may stem from the fact that foods like fish burgers are typically made from white fish which is low in omega-3 fats.
It’s estimated that about 20 percent of adults age 65 and up who are free of silent infarcts will develop at least one within five years. It may well be worth trying to eat at least 2 portions of oily fish per week in order to boost health. If you are not a regular eater of oily fish you may seriously wish to consider a supplement. A fish oil supplement providing 250-350mg EPA and 250-350mg DHA a day could be useful. For vegetarians a flaxseed oil supplement providing 500-1000mg alpha linolenic acid a day could be helpful. There are a few vegetarian DHA and EPA supplements now being produced from algae, these are difficult to find in the UK at the present time but I think they will become more available in the next year or two.
The studies were carried out in those aged over 65, just think what the benefits could be over a lifetime of good omega 3 intakes!
(1)Lindberg M et al. 2008. Long-chain n-3 fatty acids and mortality in elderly patients. American Journal of Clinical Nutrition. 88:722-729
(2) Virtanen JK et al. 2008. Fish consumption and risk of subclinical brain abnormalities on MRI in older adults. Neurology. 71: 439 – 446.
Written by Ani Kowal