A little bird told me
Manufacturers of chicken essence have claimed for years that their brews are good for improving brain performance, increasing energy levels and keeping stress at bay.
According to Vivien Chou, founder of Integrated Chinese Medicine Holdings Ltd, in traditional Chinese medicine, chicken essence is categorised as a qi tonic that can promote good digestion, enhance vitality, and replenish marrow in the bones and brain.
'Chicken meat is sweet and warm in properties, and mainly manifests its actions in the stomach and spleen,' says Chou.
New research claims to reveal how chicken essence works. The Brand's Brain Research Centre, a Singapore facility set up by the manufacturers of Brand's Chicken Essence, says it has identified a new compound - a dipeptide, produced when proteins are digested - in chicken essence that improves mental performance. They call it ProBeptigen.
According to Brand's, ProBeptigen does not occur naturally in chicken meat. It is produced through the chicken essence manufacturing process, which involves hot water extraction from chicken meat under high pressure.
The centre's Dr Paramjeet Singh presented the findings at the Asian Congress of Nutrition in Singapore a few months ago. Singapore-based Cerebos, which produces Brand's products, and Japan's Suntory Group, its parent company, have filed patents for ProBeptigen. The report has been submitted to journals, but when asked for the publication titles, a Brand's spokesman says the scientists are 'concerned about sharing their research ahead of it being published'.
However, with a lack of independent studies to back it up it is perhaps best to proceed with discernment.
In TCM theory, Chou, who was not involved in the Brand's study, says tonics such as chicken essence are for those experiencing general weakness, with symptoms like prolonged diarrhoea, heavy menses, emaciation, hot flashes and night sweats. 'They are not suitable for people during an acute or active stage of disease, such as cold and flu with fever, chills, runny nose and cough, as they may make the body react more fiercely, leading to a worse condition,' says Chou.
The Brand's dipeptide study, involving 60 people aged between 35 and 55 years old, claims the compound promotes optimal levels of serotonin, a neurotransmitter that regulates mood, appetite, sleep, memory and learning, among other things. Prolonged stress causes serotonin levels to drop, and could lead to concentration and attention problems, chronic fatigue, poor sleep and low self-esteem.
Study participants took either a placebo or a daily dose of 45 micrograms (mcg) or 90mcg of ProBeptigen for up to six weeks. They then did a series of learning and memory tests. Those who took ProBeptigen demonstrated enhanced performance in all the tests, with the 90mcg group performing the best.
'ProBeptigen helps restore the neurotransmitter equilibrium that has been disrupted, overcoming the negative effects of stress in the brain,' says Dr Keiichi Abe, vice-president of the regional research and development division of Cerebos Pacific Limited.
A separate study by a different team of scientists also found that ProBeptigen increases blood flow to the brain, boosting function.
Twelve healthy subjects with an average age of 62 years took either essence of chicken or a placebo for four weeks, followed by a two-week wash-out period. They then switched to either a placebo or chicken essence for another four weeks, depending on what they took in the first phase. The subjects' brain activity was measured through near-infrared spectroscopy and cognitive tests.