The meta-analysis funded by BRAND’s Suntory Asia, was conducted by researchers from the National University of Singapore and the National University Hospital of Singapore. It was recently published in Nutritional Neuroscience.
The researchers studied the effects of consuming essence of chicken daily by analysing seven RCTs and found that it could improve working memory.
Working memory is linked to tasks such as verbal comprehension, information retrieval from long-term memory, and reasoning tasks crucial in causal knowledge system. It is also seen as an indicator of academic success.
The seven RCTs were selected from six databases, namely PubMed, CINAHL Plus, Medline, Cochrane Library, EMBASE, and PsychINFO.
In the seven RCTs, the duration of the experiment ranged between seven and 28 days with the intervention group being provided with either 70ml or 140ml of liquid essence of chicken daily.
The placebo group, on the other hand, was given a milk protein casein liquid with caramel colouring added.
A total of 23 neuropsychological tests were performed in the seven RCTs. Examples of these tests include comprehension test and letter number sequencing.
“Daily EC consumption could serve as an excellent acute strategy to enhance working memory and the overall quality of cognitive performance to support our highly competitive society today.
“This could be especially valuable for the older population given the inevitable age-related decline in working memory,” the researchers concluded.
However, because the RCTs analysed mainly involved a younger population, the researchers said that caution ought to be exercised when it comes to the translation of these results to older adults.
Lower stress, better cognitive function
The researchers suggested that the essence of chicken improved working memory by increasing the metabolism of cortisol.
High levels of serum cortisol concentrations has been associated with the poorest attention, visual perception, and executive function.
They explained that the essence of chicken had led to better cognitive function by speeding up the metabolism of cortisol and increasing blood flow.
“According to our meta-analysis, the statistically significant improvements in working memory were observed across both the subgroup which was identified as stressed as well as the overall pooled results.
“Nonetheless, it should be recognised that the consequence of stress is complex, affecting numerous other biological pathways such as hormonal and immunity regulation.”
Another possible explanation is that essence of chicken could have strengthened working memory by stimulating or increasing the resources for dorsolateral prefrontal cortex (DLPFC) function, the part of the brain that is linked to working memory.
This is because during the neuropsychological tests, the intervention group showed a specific activation of DLPFC.
On the other hand, although the working memory was improved, the researchers pointed out that there was no marked change in short-term memory and attention.
The researchers suggested that the cognitive enhancements could be due to the “unique composition of micronutrients and bioactive compounds including the vitamins, minerals, amino acids and peptides.”
These includes amino acids histidine, carnosine, and anserine, which have shown to improve working memory, self-rated perception of “clear thinking”, “attentiveness”, and episodic memory.
The researchers pointed out that while the meta-analysis demonstrates that essence of chicken may offer acute benefits to working memory, its effects of long-term administration remain to be clarified.
This is because the RCTs analysed involved a short intervention period at between one and four weeks.
Also, the influence of other factors, such as the subject’s age, education level, occupation, the level of anxiety, and social activity in influencing the efficacy of chicken essence’s is still unclear. As such, further research is required.
Source: Nutritional Neuroscience
Daily consumption of essence of chicken improves cognitive function: a systematically searched meta-analysis of randomized controlled trials
Authors: Darel Wee Kiat Toh, Chun Hong Wong, Johnson Fam, and Jung Eun Kim