Total Recall

Nestlé recently signed a £10.6M five-year deal with the Swiss Brain Mind Institute in Lausanne to help get its head around foods that boost children's development and prevent dementia - both of which soya is said to assist - while UK ingredients supplier S Black and Israel's Lipogen claim to be working with "major" manufacturers on incorporating the soy lecithin-derived lipid phosphatidylserine, variously described as "the memory molecule" and the "brain vitamin", into mainstream products.

To put the brain drain into context, by 2040 it's estimated that 81.1M of us worldwide will have slipped into cognitive decline - up from around 24.3M today. The current indirect cost of looking after Alzheimer's sufferers in the US alone is more than £50bn while the UK spends around £7.5bn in care, dwarfing its annual obesity bill by some £6bn. Meanwhile, the links between diet and learning disorders are driving more and more parents into high street health food stores where the fastest sellers are children's pills.

Although it takes a leap of imagination to put soya on the same, albeit sometimes wobbly, pedestal as the "smart" fat omega-3, for which there is substantially more evidence, phosphatidylserine (PS), soy isoflavones, and soy polyphenols, are all thought to play a part in brain function, leading some ingredients manufacturers to make MENSA-sized claims, although only one compound - PS - has so far won qualified backing from the US Food & Drug Administration for guarding against dementia, and none has been tested under the new European Nutrition and Health Claims Regulation.

"Claims are pivotal to the success of an ingredient," admits Dirk Cremer, manager of regulatory and scientific affairs at Cargill Food Ingredients' Bioactives division. Cargill recently bought Degussa's Leci-PS and Leci-Choline, soy actives which are a precursor for neurotransmission. Several manufacturers have PS-enriched food products waiting in the wings, claims Cremer.

But given that PS is bleeping nowhere near as loudly on the consumer radar as omega-3, his colleague Roland Rabeler, Bioactive's manager for strategic projects, admits it will need a lot more than Europe's scientific stamp of approval to make the active mainstream. "It's more potent than omega-3, but there aren't so many PS manufacturers in the world and unfortunately PS is a bit more expensive," he says. For "a bit more" read 10 to 20 times dearer, although concentrations are less.

Nevertheless, with the price of omega-3 DHA (docosahexaenoic acid) likely to increase as fish stocks decline and a big question mark remaining over public acceptance of GM engineered plant-based DHA, manufacturers could well be looking for a clean replacement. "We've put PS into dairy, bakery and sweets, but it's not stable in an acidic environment," says Lipogen chief executive David Rutenberg, which, somewhat ironically, rules out PS being incorporated in one of the biggest health food categories - juices and smoothies.

Formerly extracted from bovine brains, now exclusively derived from soya, PS is touted by a number of ingredients firms as the clever nutrient which can not only help you remember where you last left your glasses, but also has a neuro/physical effect on muscle fatigue, potentially extending its application to performance enhancing power foods. While fatty acids keep the channels of communication between cells open by making sure their membranes are permeable, PS is key to firing off the internal metabolic emails while also picking up external messages and delivering them to the cell core. But, while the anatomic evidence is sound, the dietary effect PS has on specific disorders, such as Alzheimer's, is far from conclusive, says Dr Fred Brouns, a leading expert in the field, and fellow researcher at Cargill, who's less optimistic that we'll see PS on functional food labels any time soon.

"There's evidence to suggest that PS has a beneficial effect on cognitive function, but we need further substantiation. We need controlled clinical trials in a substantial number of subjects. These are very expensive and I think PS will be stuck in supplements as long as there's no very good substantiation."

Given the controversial recent history surrounding soya, neither are food manufacturers convinced such claims will have any positive impact on the market. In fact, overloading soya with too many intelligent attributes could be a dumb move, according to Robin Gleave of Soy Health Foods, a subsidiary of soy lecithin supplier Soy International."It's not a claim I would feel comfortable making. There's a danger for manufacturers that they start to make this sort of claim and then their credibility gets shot to hell. We try to steer a diplomatic path and stick to the main one that it lowers cholesterol."

That said, the market for brain food is growing. And a key target may be women. Professor Eva Hogervorst of the University of Loughborough (UK) has spent the past year trying to work out why eating fermented soya (tempe) appears to help us keep our senses, while consuming unfermented soya (tofu) can leave us dazed and confused. The female factor is important because of the links between estrogen in post-menopausal women or those taking hormone replacement therapy and the phytoestrogens contained in soya called isoflavones.

Italian research last year concluded that soy isoflavone supplements made women of a certain age less forgetful and prone to mood swings, while trials in Honolulu found high tofu consumption produced a higher risk of dementia in both men and women, but the effect of tempe is new and Hogervorst's study, which looked at the dietary effect of soy on several hundred elderly people in Indonesia, has come up with remarkable results.

"Those who ate tempe more than once a day had a 10 times lower risk of memory impairment, one of the first signs of dementia, but people who ate tofu had a higher risk," she says.

"That's similar to what we were finding in estrogen - women over 65 who have high levels of estrogen or who were treated with estrogens for a long period of time were at risk of dementia. Estrogens have a chemical structure which is much like phytoestrogens. High levels of phytoestrogens in soya may have the same type of pattern as estrogens, but what happens during fermentation of the soya necessary for tempe is that a lot of folic acid is produced by the moulds. So even though phytoestrogen levels are high in tempe, because folic acid is also high they might be protected."

The effects are fast and impressive. "What we see with these hormones is that they react very quickly - within 24 hours, neurons in the cells start sprouting." Which means the brain neurons literally regrow their potential to communicate, not only halting, but potentially reversing the decline that will see many of us lose up to three-quarters of our memory and cognitive function by the age of 75. "We have seen memory improvements within 24 hours of soy treatment."

But that's not the end of the story, says Hogervorst. "The effects are the same in men and women. However, rather than to focus on supplements, more research now needs to be done into dietary patterns of people with less dementia prevalence, which is lower in the east than in the west. Diets with lots of fruit and red, orange and dark green veg which contain phytoestrogens and folic acid but perhaps also a factor X we don't yet know about seem to lower the risk."

While a limited number of food products in mainland Europe, most notably confectionery, already boast mood enhancing benefits from soy, bigger things are expected from the little bean as manufacturers move towards nourishing the mind as well as the body. "If you look at Nestlé, it wouldn't have invested so much money just to get basic scientific answers; they want products on the market," says Cargill's Rabeler. "If the regulatory terms are clear it might be quite soon."

Printer friendly version

Email this article to a friend