In particular, studies into how nutrition and food determine our mental well-being are garnering insights that could be harnessed to promote mental fitness.
The power of polyphenols is a case in point. As more knowledge is gathered about these compounds, efforts to optimise bioavailability in future formulations can become more tailored and precise in function.
“The ability of polyphenols to impact upon memory appears to be, in part, underpinned by their ability to interact with the molecular and physiological apparatus used in normal memory processing,” said Dr Julien Bensalem, innovation project manager at Activ’Inside, a French company specialising in botanical ingredients and formulations for nutrition and well-being markets.
Bensalem’s research into the effects of polyphenols on age-related cognitive decline has led his team to investigate how a polyphenol-rich extract from grape and blueberry could affect spatial learning in middle-aged mice.
Crucially, the team were targeting the hippocampus, a major component of the brains that consolidates information from short-term to long-term memory and controls spatial navigation.
Results indicated that a polyphenol-rich diet could be an efficient nutritional way to prevent age-induced cognitive decline.
“We observed interesting results in adult mice, with an improvement of spatial learning and an increase of neurotrophine in the brain without any deficit observed,” he noted.
“Based on results in rodents and arguments from epidemiology I would say an increased intake of polyphenols at whatever age could be a good way to prevent cognitive decline.”
“Moreover, executive functions, more so than memory performances, which can be impaired in daily life by stress or tiredness, have also been shown to be improved in adult by polyphenol intake.
Multi-functional nutrients
Bensalem’s comments allude to a compound that may have a multitude of health benefits that could manifest over the longer term. It’s a feature shared with such nutrients like omega-3s, caffeine and members of the micro-nutrient family.
Research has demonstrated that short term administration of nutrients is of benefit in cognitive function or mood. However, benefits of optimised nutritional status are less clear due to the difficulty in assessing their effects over a longer period.
Prof David Kennedy, director, Brain, Performance and Nutrition Research Centre at Northumbria University, has been using a technique known as near infrared spectroscopy (NIRS).
The technique is a non-invasive optical imaging technique used to monitor brain blood flow following the short and long-term administration of caffeine, polyphenols and omega-3 polyunsaturated fatty acids.
“Trials in which the effects on cerebral blood flow following administration of dietary components have successfully demonstrated NIRS as a sensitive measure of change during cognitive tasks in both acute and chronic treatment,” said Professor Kennedy.
“NIRS has also been particularly valuable for the evaluation of cognitive function across the lifespan as well as in abnormal functioning.”
Long term NIRS use
With the growing interest in the contribution of nutrition to cognitive health across the lifetime, Professor Kennedy believes that the application of NIRS in the field of nutritional neuroscience is a valid and natural extension of the technique.
He referred to a study that used NIRS to demonstrate a prefrontal decrease in total haemaglobin (Hb) during task performance following a dose of caffeine (75 mg).
“The study benefitted from continuous monitoring during the absorption and testing periods as well as increased statistical power resulting from monitoring NIRS outcomes,” the study noted.
NIRS has also been applied to chronic intervention studies. A study that assessed the effects of 12 weeks’ administration with fish oil in healthy young adults (18–35 years) revealed that administration with docosahexaenoic acid (DHA)-rich fish oil, but not eicosapentaenoic acid (EHA)-rich fish oil, was associated with task-related increases in oxy-Hb and total Hb.
Vitafoods Europe 2016
Both Dr Bensalem and Professor Kennedy will be at Vitafoods taking place in Geneva next month. As part of the Cognitive Health session on the 10th May, Dr Bensalem will present updates to a new patent-pending polyphenol formulation that shows learning and memory improvements when given to elderly subjects.
Professor Kennedy will discuss research that both vitamins and polyphenols can control several physiological functions relevant to healthy brain ageing, including cerebral blood-flow and brain metabolic parameters.