Previously, in the Journal of Natural Health Solutions we reported on research findings, that have revealed a protective effect for the carotenoids lutein and zeaxanthin against eye-related damage, caused by exposure to high-energy blue light from computer or smart phone screens. Researchers found that these two carotenoids act as a natural filter for high-energy blue light.
Now, hot-on-the-heels of this research, lutein and zeaxanthin are back in the spotlight once again…. lutein in particular.
Dr. Naiman Khan, a professor of kinesiology and community health at the University of Illinois, and his fellow researchers, have discovered that a high intake of lutein and zeaxanthin-rich leafy green vegetables could help slow down age-related cognitive decline.
The researchers also believe this habit may provide brain benefits in early to middle adulthood before the onset of old age. Because lutein accumulates in the brain, researchers are able to measure levels of this primary carotenoid without having to use invasive techniques.
Lutein’s role in working memory, brain processing, functioning and speed has long intrigued researchers, as it is a nutrient that the body cannot make on its own, which is why upping your intake through diet or supplementation is so important.
The study involved 60 healthy adults aged between 25 and 45. Carotenoid levels were assessed by measuring macular pigment optical density (MPOD), a reliable indicator of lutein levels in the brain. Event-related brain activity was recorded during the performance of cognitive control tasks and used as an indicator of cognitive function.
Results showed that across all subjects MPOD was related both to age and to the specific electrical brain activity during the decision-making process, known as the P3 wave.
Although younger adults exhibited larger P3 amplitudes than their older adult counterparts, older subjects with higher MPOD levels displayed P3 measurements similar to their younger adult counterparts in amplitude. Further analyses showed that age was no longer a significant predictor of P3 amplitude when MPOD was included as a predictor in the model.
Commenting on the findings, researcher Anne Walk, a postdoctoral scholar, said: “The neuro-electrical signatures of older participants with higher levels of lutein looked much more like their younger counterparts than their peers with less lutein. Lutein appears to have some protective role, since the data suggest that those with more lutein were able to engage more cognitive resources to complete the task.”
These results are similar to previous research findings – including those that have focused on older and middle-aged adults in whom a period of decline has already set in – that have shown a strong link between MPOD and enhanced neuro-cognition.
MPOD is known to be directly related to a healthy diet. Anne Walk added: “We want to understand how diet impacts cognition throughout the lifespan. If lutein can protect against decline, we should encourage people to consume lutein-rich foods at a point in their lives when it has maximum benefit.”
To increase your intake of lutein and zeaxanthin, eat more leafy green vegetables, courgettes, garden peas, avocados, Brussels sprouts, eggs, and dark-coloured fruits like berries. Alternatively you can take lutein and zeaxanthin in supplement form – normally obtained from bilberry extracts – at a dose of 150mg a day.
Here's to your good health,
Journal Of Natural Health Solutions
Frontiers in Aging Neuroscience, published online ahead of print: doi.org/10.3389/fnagi.2017.00183