Are you familiar with that moment when you are having a conversation, knowing exactly what you mean, but the word simply refuses to emerge? It turns out that the solution might just be in your meal, and particularly in the combinations that characterize the Shavuot holiday table.
Lutein is an antioxidant from the carotenoid family that is known to many primarily in the context of eye health and protection against blue light radiation. However, studies from recent years reveal that it is one of the few components that manage to cross the blood–brain barrier and accumulate selectively in brain tissue. The unique and interesting thing is that the level of lutein in the brain was found to be linked to cognitive function much more than its level in the blood.
What does this actually mean? It is not just a "passerby", but apparently plays an active role in the communication between nerve cells.
Studies show that high levels of it are associated with better information processing speed and a significant improvement in Verbal Fluency – that smooth "word retrieval" ability that we all strive for.
2 super interesting studies on the subject
The first was published in the journal Frontiers in Aging Neuroscience. Researchers examined a group of older adults and discovered that those with high levels of lutein in the brain (measured via macular pigment optical density, which is like a "window" to the concentration of lutein in the brain) showed neural activity similar to that of individuals significantly younger than them.
The study found a direct link between lutein levels and the ability to use knowledge, skills, and linguistic wealth acquired over years. Those with high lutein levels demonstrated better "word retrieval" and linguistic knowledge, even under the effects of age.
The second study, published in the Journal of the International Neuropsychological Society, examined the relationship between carotenoid concentrations in the brain (post–mortem tests that verified the data) and the cognitive abilities measured in the subjects during their lives. The researchers discovered that among all carotenoids, lutein was the most significant component found to correlate with brain function.
Of course, a significant link was found between lutein levels in the brain and performance in verbal fluency tests. The subjects with the higher lutein concentration in the brain managed to retrieve words more quickly and perform tasks of naming (giving names to objects) and fluent speech in a significantly better manner compared to those with low levels.
To understand the uniqueness of lutein, it is worth comparing it to another popular brain component – Magnesium L–Threonate. This type of magnesium was found to help memory and word retrieval problems.
While Magnesium Threonate acts primarily on the plasticity of the brain (the ability of synapses to form new connections and strengthen learning), lutein acts as a "shield" and a conduction enhancer. It reduces oxidative stress and inflammation within the neural networks associated with language processing. Magnesium helps the "hardware" of the brain work better; lutein improves the flow of information within the "software" of language and memory.
Beyond lutein, we have heard quite a bit about additional antioxidants such as anthocyanins (found in berries) and flavanols (in cocoa). The central difference is that lutein is preserved over time in brain tissue, while other antioxidants sometimes act in a more localized manner on blood flow to the brain. The combination between them is what creates peripheral protection for our cognitive abilities.
How to get your lutein?
Lutein is found in abundance in green leafy vegetables and cruciferous vegetables like spinach, kale, chard, parsley, broccoli, peas, and avocado.
In addition, egg yolk is a particularly important source, since the egg also provides choline – a precursor for the neurotransmitter acetylcholine, which is responsible for short–term memory.
Lutein is a fat–soluble component (Lipo–soluble). If you eat a green salad without a drop of fat, most of the lutein in it will simply not be absorbed by the body. And this is where the winning connection comes into play: A combination of green vegetables with dairy products.
The fat in cheese: Milk protein and the fat in cheeses (Bulgarian, feta, parmesan) dramatically improve the availability of lutein.
Gentle cooking: In contrast to certain vitamins that are destroyed by heat, short cooking or sautéing of spinach and broccoli actually breaks down the cell walls of the plant and releases the lutein out, so that it will be available for absorption.
A winning dish: Spinach and cheese quiche or green lasagna are ideal combinations – they contain lutein from the spinach, lutein and choline from the eggs, and fat from the cheese that locks in the absorption of them all together.