No one who watched a recent UK TV documentary that followed in forensic, unflinching detail the humiliating descent into dementia of one ordinary family man can fail to be haunted by the cruel, protracted mind games that Alzheimer's plays on its victims. Nor by the frightening statistic that 60,000 people die from dementia each year in the UK, with many thousands more across Europe.
"The one thing people worry about most is losing their marbles. They almost take that more seriously than cardiovascular disease," says Dr Ann Marie Minihane of the University of Reading in the UK, and a specialist in the effects of long chain polyunsaturated fatty acids on the heart and the brain.
And, if we're worried, public health administrators are even more vexed because the cost of propping us up as we persist into an increasingly doddery old age could make the obesity bill look like small change. With one in five people reaching 60 by the middle of the hose already suffering mild to moderate Alzheimer's.
The study is not before time, says Minihane at Reading. "We cannot get at the brain. It's a difficult tissue to assess. Most of the data for cognitive decline is just association trials and it's difficult to prove which is the chicken and which is the egg - is the disease affecting omega-3 levels or the other way around?"
Laboratory tests on genetically modified mice suggest that DHA may delay or even prevent Alzheimer's by blocking the accumulation of two key proteins, tau and beta amyloid, associated with the formation of tell-tale brain lesions, known as tangles and plaques.
But that's not the whole story. Parallel studies in the US suggest that eating antioxidant-rich foods could also help people think straight and may even help reverse the ageing process, since the brain is particularly vulnerable to oxidative stress, but has the unique capacity to regrow, albeit more slowly, as we get older.
Boosting the grey matter
Scientists at the US government's Agricultural Research Service believe that foods such as blueberries could help clear the neural pathways that allow brain cells to communicate. And it's those signals that facilitate the conversion of short-term to long-term memory. It's not just mental agility, but physical co-ordination that can be improved, although researchers stress that brain nutrition is an emerging science and thousands of other compounds influence the body's ability to put antioxidants to use. Phytochemicals and essential nutrients may produce a cocktail of effects that are not yet fully understood. "But it's feasible that continued research in this area will point to dietary regimens that are effective in boosting neural function," the say the researchers.
Martek Biosciences, which donated algal DHA for the American experiment that concludes next autumn, believes there's mounting evidence to suggest it also prevents age-related macular degeneration, the most common cause of blindness in elderly people, which echoes a theory that early changes in the eye could signpost susceptibility to dementia.
Omega-3 is already known as an essential building block for visual development in infants, but Minihane is cautious. "When it comes to the other way round - the decline of visual function - that's an area of relatively new research," she says. But she concedes: "If you take a fat profile of the eye, the levels of fish oil fats are particularly high, as they are in the brain, so they must be important to these tissues.
"But with cardiovascular disease and omega-3 fatty acids, the jury has come back positive. It's now just a matter of dose and what you need to achieve the benefits. If you take relatively low doses of EPA and DHA it improves your survival following a heart attack. At higher doses, fish oils will reduce your likelihood of having one in the first place," says Minihane.
Which begs the question, when do you start? "When you talk about CVD (cardio-vascular disease) the earlier the better - late 20s certainly," says Minihane. "With cognitive decline it's a bit harder to say."
And that opens up a can of marketing worms. How do you persuade someone in the prime of their youth that it could all go decidedly downhill by the time they're 60, unless they think about diet now?
According to Greg Tucker of The Marketing Clinic in the UK, brands need to build a repertoire of products that carry consumers from the cradle to the grave. In other words, "a life stage strategy" that conveys the benefits through intelligent formulation rather than on-pack messaging.
"Eat up, it's good for you, is possibly the worst sales pitch designed by man," says Tucker. "And 'Good for you' is not a motivating factor, it's the broccoli moment," says Tucker. Instead, products that deliver health benefits tomorrow should be sold by stealth, he argues, even if that verges on the realms of sensory deceit.
He claims big brands are already "training the palettes" of consumers to move unconsciously through their portfolios of subtly enhanced products. They don't need to know it's good for them, or, as he puts it: "There's no point trying to sell a 19-year-old male a Volvo, because security is not a motivating factor when you're 19."
Life stage nutrition
Belgium fruit juice maker Sunnyland credited its mature customers with a little more intelligence when it introduced its lifestage Benefit juices for the over-50s last year, including calcium-enriched, cholesterol-lowering and immune-boosting varieties, all aimed at addressing key health concerns among the elderly.
"We explained it to doctors and put fliers in waiting rooms, so patients could see our products and ask for comments from their practitioner," says Charlene Simermann, marketing officer for Sunnyland Belgium. Next year, she hopes to take part in a health authority co-ordinated give-away, which will see food and medicine targeted at the over-55s delivered to their doors.
"It's the first time we have put something like this on the market, but we are thinking of other products," says Simermann.
The older you are, the more relevant life stage marketing becomes, believes Alex Smith, md of UK muesli maker Alara, which launched a complete LifeStage nutrition range last year. But all but its Prime Years muesli for the over-40s were a sales failure. Smith puts this down to the fact that "the older you get, the more you think about what you eat"
Senior moments
''Pressure's off - studies at King's College London among 38 middle-aged subjects with an average age of 49 showed that omega-3 DHA taken at less than 1g a day reduced diastolic blood pressure by an average of 3.3mmHG and increased DHA levels in red blood cells by 58%.
Know your onions - Japanese scientists at Hokkaido Tokai University claim to have found a link between eating lightly cooked onions and improved memory. They believe a suphur-containing compound in the onions helps flush the brain of harmful toxins.
Inhale deeply - smoking might help reduce chances of developing dementia. Studies show that the oxidative stress induced by nicotine stimulates antioxidant activity, which is good for the brain.''
For details of ''FIHN's Life Stage Nutrition conference, click here''