New research suggests that upping your consumption of carotenoids could enable your brain to work more efficiently and even slash your risk of developing dementia.
Researchers at the University of Georgia looked at the brain activity of 40 over-65s in an MRI scanner as they attempted to recall previously presented pairs of words. Participants with higher levels of carotenoids (specifically, lutein and zeaxanthin) in their systems showed less brain activity, suggesting that their memory processing was more efficient and less effortful. Those whose brains had lower levels of the nutrients to draw on were forced to rely on less efficient compensatory measures, say the researchers.
Previous research has linked higher blood lutein levels with a decreased risk of developing dementia and Alzheimer’s disease, whilst scientists who carried out a long-term study on the association between diet and dementia risk have declared that the consumption of foods rich in lycopene (another form of carotenoid) may delay cognitive ageing by 1-2 years.
Need another reason to reach for the kale chips? Lutein and zeaxanthin
are also said to protect against age-related macular degeneration and
help to maintain eye health in older adults.
So which foods should you be throwing in your shopping trolley?
You probably associate the term carotenoids with orange fruits and vegetables – the likes of sweet potatoes, butternut squash and, well, carrots. You might be surprised to learn, then, that lutein and zeaxanthin are most commonly found in green and yellow fruit and veg. They are also the substances responsible for the yellow pigmentation of egg yolks.
Kale is the richest source, but spinach, kale, lettuce (especially Romaine lettuce), turnip and collard greens, broccoli, courgettes, garden peas, Brussels sprouts and okra are good alternatives.
Lutein and zeaxanthin are also found in sweetcorn, carrots, tomatoes, oranges, melon, grapefruit and, of course, eggs.
Lycopene is responsible for the red colouring of many fruits and vegetables. Good sources of the nutrient include guava, watermelon, tomatoes (preferably cooked), papaya, grapefruit, red peppers, red cabbage, mango, carrots and asparagus.