Feed your mind

Few market researchers would dispute that 'mood foods' could deliver big bucks for the food industry, says Dr Mike Green, a former clinical psychologist at Unilever. But research in this emerging field is still embryonic, despite a steady stream of product launches claiming to boost children's exam results, calm nerves after a long day, or re-energise weary grey matter.

Green, who has just persuaded the UK's Aston University to part with the cash to establish a facility to study the effects of food on the brain, is confident of seeing a return as manufacturers searching for the next big thing in functional foods queue up to test the efficacy of their ingredients.

The evidence for many of them is mixed at present, he admits. "Things are changing so fast. There is a lot of research into omega-3, green tea, folate, gingko biloba and some other ingredients, but less into some you already see on shelf.

"I remember doing a report into PS [the soy-based memory molecule phosphatidylserine] for the Advertising Standards Authority 10 years ago. The evidence was unremittingly awful, although things have probably moved on since then.

"Far more research is needed if companies want to make claims under the new European Nutrition and Health Claims Regulation."

Kitted out with facilities for collecting blood, urine and saliva samples, Green's lab can test for glucose, iron, cortisol, cholesterol, haemoglobin, zinc protoporphyrin, 5-HIAA [serotonin function] and potassium.

Users will also have access to glycaemic index (GI) testing and body composition analysis, plus brain scanning facilities, including EEG (electroencephalogram), MEG (magnetoencephalogram) and MRI (magnetic resonance imaging).

Mind games

Data from trials in this field often throws up baffling results, Green admits. In one such study, he gave volunteers drinks sweetened with glucose and others drinks with added aspartame. As expected, those who consumed the drinks with glucose performed better in mental agility tests, whereas the performance of those who consumed the drink with aspartame did not.

However, those who drank the glucose drink but were told it contained an artificial sweetener - did not register any improvement, he says. "In other words, what you think something will do to your mind has a large bearing on whether it will."

Similarly, consumers typically self-report that brightly coloured drinks make them feel more alert than dull-coloured drinks, he points out.

"The bizarre thing is that objective measurements show that they are actually right."

So where does this leave companies looking to make health claims about omega-3, creatine, CoQ10, green tea, guarana, ginseng, cocoa polyphenols, folate, gingko biloba and gamma- aminobutyric acid (GABA), all of which are claimed to influence mood and brain function?

In reasonably good stead, insists Green. "There are established ways for people to provide a subjective impression of their mood, which you can then analyse alongside objective measures/biomarkers such as levels of serotonin [a neurotransmitter that controls mood] or cortisol [the stress hormone] in bodily fluids." There are also well-established methods for measuring reaction times, recall/memory and other measures of mental acuity, he points out.

Given the obesity epidemic and our apparent failure to deal with it, cash might be better spent looking at the effects of low fat or high protein diets on mood and the psychology of eating behaviour, he says.

"The joke is that the one strategy governments always adopt to improve our diets is labelling. If you give people the right information they will make the right choices, we are told. But this presupposes that people act rationally when it comes to food. They don't."