Older people with memory problems can boost their brainpower with fish oil supplements, say researchers. Healthy people with mild memory deficits of events in their past life, so-called episodic memory, had improved recall after six months of treatment.
A new overview says the omega-3 fatty acid DHA has most benefit for people with existing memory problems, particularly when they are coping with physical or mental stress.
Experts believe supplements rich in DHA from fish oils or other marine sources might slow or prevent mental decline as it is found in reduced amounts in people with Alzheimer’s disease.
But here have been conflicting results from studies, with some showing no benefit from supplements in dementia patients. DHA is an omega-3 fatty acid that is thought to help nerve cells communicate with each other. The richest source of the nutrient is oily fish, such as herring, mackerel and sardines.
Britons are currently advised to eat at least one portion of oily fish a week but figures show just one in three do so.
In an overview of evidence, scientists from the US and Canada said several studies had looked at DHA supplements and their effect on memory. The MIDAS study involved of 485 healthy elderly people who complained of memory problems, says a report in the journal Prostaglandins Leukotrienes and Essential Fatty Acids. The findings showed 24 weeks of taking marine oil supplements led to ‘significant improvements’ in memory test scores compared with those who had dummy tablets. ‘It appears that benefits of DHA are best observed during ageing when there is some mild cognitive impairment or memory complaint or perhaps when a person is exposed to certain chronic physical or mental stressors’ says the overview. The best dietary source of omega 3 fatty acids is oily fish because the human body cannot produce omega-3 fatty acids.
White fish is also a healthy food including cod, haddock and plaice although it contains lower levels of essential fatty acids. Dr Carrie Ruxton, independent public health nutritionist who reviewed the latest evidence for supplements manufacturer Equazen, said oily fish consumption was falling.
On average, Britons were eating around 90g weekly compared with the government’s recommended levels of 140g weekly. She said ‘Studies have variously shown that fish oils lead to better performance in working and verbal memory indicating the potential to delay the onset of cognitive decline and that supplementation with DHA could improve learning and memory function.
‘Two thirds of Briton never eat oily fish, they do not have omega 3 in their diet and supplements are a good alternative.
‘We know that people with the greatest cognitive decline have the least amount of omega-3 in their diet.’