I have a confession to make – I don’t like kale! Which is a shame because it is full of nutritious compounds that have potential health benefits. A recent study has shown that two of the health-giving compounds in kale, lutein and zeaxanthin (zee-axe-an-thin), can help to improve brain function particularly in older adults. Psychologists from the University of Georgia used functional magnetic resonance imaging (fMRI) to measure the impact of lutein and zeaxanthin on brain function. Functional MRI measures blood flow to active areas of the brain at any given time. In this trial forty adults aged between 65 and 86 years had their brain function assessed by fMRI while attempting to remember word pairings. Those with lower levels of lutein and zeaxanthin required more brain-power than those with high levels; in essence those with higher levels required less brain energy and resources to remember learned information. The researchers described those with higher levels as more “neurally efficient.”
While many natural compounds have the potential to improve brain function and have been reported on e.g. turmeric, resveratrol, fish oils etc, understanding the mechanism of action can lead to more specific interventions and thus the potential for improved cognition. The size of the study is relatively small however the variation in brain function was significant illustrating the potential for changes in diet to include more carotenoid containing compounds could help boost brain-power and cognitive performance. So the out-take from this study: include some kale and other foods rich in lutein and zeaxanthin, which include spinach and other dark green leafy vegetables, egg yolks, zucchini, kiwi fruits and grapes. These other foods I love so all good!
Despite not relishing the thought of sitting down to a raw kale salad, I do eat it on a fairly regular basis as part of a varied diet. Baby kale finely shredded in coleslaw is one way I ‘hide’ it. Another recipe I like is Kale Pesto. This particular recipe comes from www.bbcgoodfood.com but I often mix it up with added basil or parsley for variety – it is so easy to make.
- 85g toasted pine nuts
- 85g grated parmesan cheese
- 3 cloves of garlic
- 150mls quality olive oil plus extra to serve
- 85g of kale or halve the amount and add the equivalent quantity of basil or parsley
- Juice of one lemon.
- Add all the ingredients to the blender and whizz to a paste. Season to taste.
- To store put in a glass jar or container and cover the surface with extra olive oil to keep it fresh.
Cutter A. Lindbergh, Catherine M. Mewborn, Billy R. Hammond, Lisa M. Renzi-Hammond, Joanne M. Curran-Celentano, L. Stephen Miller. Relationship of Lutein and Zeaxanthin Levels to Neurocognitive Functioning: An fMRI Study of Older Adults. Journal of the International Neuropsychological Society, 2016; 1 DOI:10.1017/S1355617716000850