Curcumin is a polyphenolic compound isolated from the roots of Curcuma longa, from which turmeric is prepared and used widely as a coloring agent, food additive, and traditional Indian and Chinese medicine.
For decades curcumin and related bioactive curcuminoids have been the center of interest in scientific studies worldwide into their therapeutic potential. One of the effects it has been investigated is the potential neuroprotective benefits.
In a recently published study, researchers performed a cohort study on a population of middle-aged and older adults from the Singapore Longitudinal Ageing Study (SLAS). They evaluated the consumption of dietary curcumin and its neuroprotective effects. The study was published in the journal Nutrients.
Effects on Gut-Brain Axis
The study included 2,804 participants in Southeast Singapore from September 2003 to December 2004 and 3,270 participants in Southwest Singapore from March 2009 to June 2013.
At baseline and follow-up interviews, the participants were asked how frequently they consumed curry in their meals. Never or rarely (less than once a year), occasionally (at least once/year to less than once/month), often (at least once/month to less than once/week, very often (at least once a week), or daily.
Global cognition was assessed using a locally translated version of the Mini-Mental State Examination (MMSE) which was previously validated for use among Chinese and non-Chinese (Malay, Indian and others) Singaporean older adults. Also, neurocognitive tests were used for the assessment of cognitive domains.
The study included participants with a mean age of 65.9 years and 63.6% were women. The participants who reported higher levels of curry consumption were more likely to be younger, men, of non-Chinese ethnicity, better educated, and with higher levels of education.
Increasing levels of curry consumption were significantly associated with better crude estimates of mean neurocognitive performance scores at both baseline and follow-up.
It is well known that oral ingestion of curcumin has a low bioavailability. However, high concentrations of curcumin remain in the intestines after oral ingestion. Bacterial enzymatic actions of curcumin may form metabolites pharmacologically more active than curcumin. A hypothesis is that curcumin could act primarily in the gastrointestinal tract, exerting direct regulatory effects on the brain in bidirectional gut-brain communication, influencing core neurological processes.
The researchers concluded that consumption of dietary curcumin was associated with the maintenance over time (4.5 years) of higher functioning on attention, short-term working memory, visual-spatial constructional ability, language, and executive function.
Tze Pin Ng, et al. Curcumin-Rich Curry Consumption and Neurocognitive Function from 4.5-Year Follow-Up of Community-Dwelling Older Adults (Singapore Longitudinal Ageing Study). Nutrients. 2022. 14(6), 1189; https://doi.org/10.3390/nu14061189