There’s some scientific evidence omega-3 may have some real health benefits, but it’s not necessarily a magic brain pill.
Epidemiological studies. A growing body of evidence from epidemiological (population) studies suggests that eating omega-3s — specifically the long-chain fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), but DHA in particular — decreases the risk of cognitive impairment and dementia.
(NB: Cognitive impairment ranges from mild to severe, at which point it may be diagnosed as dementia. With mild cognitive impairment, a person has problems with memory, language or another mental function that are severe enough to be noticeable to other people, but not serious enough to interfere with daily life.)
Epidemiological studies can show statistical relationships between elements of diet and illness or mortality — salt intake and high blood pressure, for example — and the evidence is often used to advocate public health interventions such as dietary changes. But, unlike clinical trials, they don’t conclusively show cause and effect.
Clinical trials. The UK-based Cochrane Collaboration conducted a systematic review of research in 2012, looking for randomised, controlled clinical trials of omega-3 supplementation in healthy older adults that might support the evidence from epidemiological studies. It found two trials that met its selection criteria and the conclusion is that the studies show “no benefit for cognitive function with omega-3 PUFA supplementation among cognitively healthy older people. Omega-3 PUFA supplements may have other health benefits, and the authors comment that consumption of fish is recommended as part of a healthy diet.”
DHA and EPA may reduce the risk of heart disease and increasing your omega-3 intake may provide other health benefits. Given the encouraging results from epidemiological studies that omega-3 may also protect against dementia, it’s worth making sure that you’re getting enough.
How much is enough?
To lower your risk of chronic disease, the National Health and Medical Research Council (NHMRC) suggests a dietary target of 430 mg of omega-3 fatty acids a day for women and 610 mg a day for men. You need to eat at least two fish meals (preferably oily fish) per week to get this much, and omega-3 in fish, below, shows which sources are best.
But a recent seafood consumption survey found that more than three quarters of us eat less than this amount. If you’re in this category, fish oil supplements could be an option.
Omega 3 in fish
Fish vary a lot in how much omega-3 they deliver. To give you some guidelines, the diagram below compares the amounts of omega-3 per 150 g serve from the species of fish you're most likely to find in your local supermarket or fish shop.
Ginkgo biloba is one of the world’s oldest living tree species. It’s been used medicinally for many centuries, and herbal ginkgo supplements are particularly popular in Europe and the US.
Ginkgo is promoted as a ‘smart’ drug to enhance the brain power of healthy people. But there's little evidence that it actually works.
A systematic review published in 2007 looked at 15 randomised controlled clinical trials of ginkgo for cognitive function, carried out in healthy people aged under 60. The majority of studies used subjective ratings (self-reported improvement in memory, for example) to measure effect. Of these, only one of five single-dose studies and one of six longer-term studies reported any significant positive results, and the review concluded there was no convincing evidence for a strong positive effect of ginkgo on any aspect of cognitive function in healthy young people. Findings from studies in older people with no cognitive impairment have been mixed.
In 2008, a large study called the Ginkgo Evaluation of Memory (GEM) study - conducted over eight years and involving more than 3000 participants - evaluated whether long-term ginkgo use (120 mg, twice a day) will help prevent dementia in healthy elderly people, or those with mild cognitive impairment. According to the study; “240 milligrams per day of the dietary supplement Ginkgo biloba was found to be ineffective in reducing the development of dementia and Alzheimer's disease in older people.”
As a treatment for people with existing dementia or cognitive impairment, the evidence for ginkgo is mixed.
A 2007 Cochrane review of the scientific literature included 35 studies, the majority being 12 weeks long. The daily dose was usually less than 200 mg/day, and all studies except one used a standardised ginkgo preparation known as EGb 761. Many of the trials received funding from the company that manufactures this preparation.
Data from some trials at 12 weeks showed ginkgo to have a positive effect on cognition, but the effect was variable and shorter trials showed no benefit. The review concluded that the evidence for ginkgo being beneficial for people with cognitive impairment and dementia is inconsistent and unconvincing.
Commission E (a German government regulatory agency) approves the use of standardised ginkgo extract to treat dementia, but Alzheimer’s Australia thinks further research is needed before a definitive statement can be made about its effectiveness as a dementia treatment.
Going on the current evidence, there’s little to recommend the use of ginkgo for preventing dementia or improving memory or cognition if you’re healthy.
The herb brahmi (Bacopa monniera) has long been used in Ayurvedic medicine as a nerve tonic. Studies on rodents have shown encouraging results for the use of brahmi for improving learning and memory, but results from good-quality clinical studies are mixed.
One trial using a dose of 300 mg of brahmi over 12 weeks in 46 healthy volunteers found that it improved the speed of visual information processing, learning rate and memory consolidation.
In another three-month trial, involving 76 adults, improvements were observed in a test for new information retention, but no changes in the rate of learning.
A trial involving 38 healthy people found no changes in cognitive function, but testing was done just two hours after a single 300 mg dose of brahmi.
A further study using Blackmores Ginkgo Brahmi (containing 300 mg brahmi and 120 mg ginkgo) in 85 healthy people failed to show any significant differences in memory, attention, comprehension or learning after four weeks.
The current evidence for brahmi isn't convincing enough to warrant paying for supplements.
Diagnosing dementia and brain health
We all forget things from time to time. Who hasn’t walked into the kitchen and forgotten what they went in there for, or mislaid the car keys?
Everyone is different and the effect on memory of getting older is different for each person. But memory loss that disrupts everyday life isn’t a normal part of aging — it’s a symptom of dementia (the most common cause of which is Alzheimer’s disease), a gradual and progressive decline in memory, thinking and reasoning skills.
It’s perfectly normal to get distracted at times, and forget to serve part of a meal, for example - but a person with dementia may have trouble with all the steps involved in preparing a meal. And temporarily losing a wallet is one thing - but putting it in an unusual place like the freezer could be a warning sign of dementia.
Losing items and having trouble remembering people’s names could indicate that you have what’s been termed mild cognitive impairment (MCI). This is defined as a level of memory loss greater than that usually experienced with aging, but without other signs of dementia. People with MCI can usually accomplish all their daily tasks, but often compensate for their memory problems by relying on memory prompts such as reminder notes or calendars.
The presence of symptoms such as these doesn’t necessarily mean you have, or will develop, dementia, but it’s better to see your doctor to discuss them sooner rather than later. Early and accurate diagnosis of Alzheimer’s disease or other types of dementia can ensure you get the right treatment, care and support.
For a checklist of the early signs of dementia, go to Alzheimer's Australia, or call the National Dementia Helpline on 1800 100 500 to discuss memory concerns.
Keep your brain healthy
Eat well. Numerous studies suggest that fruit, vegetables and fatty fish might help preserve mental agility by protecting blood vessels and promoting regeneration of nerve cells. Think Mediterranean diet. Avoid harmful substances — excessive drinking and drug abuse damage brain cells.
Stay socially connected. Sports, cultural activities, emotional support and close personal relationships appear to have a protective effect against dementia.
Exercise regularly. Physical exercise is essential for maintaining good oxygen-rich blood flow to the brain.
Sleep and relax. Make sure you get regular and adequate sleep, and try to curb stress — it triggers the release of hormones that can impair memory and even damage brain cells.
Challenge yourself. Learn new puzzles, such as crosswords or Sudoku, play a musical instrument or learn a new language. Keeping mentally active strengthens brain connections, and you can train your brain to improve reasoning, memory and speed of processing.