Speaking with NutraIngredients-USA at the recent SupplySide West, Dr James Stringham from the Duke Eye Center (Durham, NC) discussed results from a recent 6-month, double-blind, placebo-controlled trial with 59 young healthy people.
“The results were very exciting,” he said. “A reasonable dose produced significant changes, improvements in attention, processing speed, composite memory – really key components of cognitive health and performance. Importantly, the placebo group stayed flat the entire way through.
“Just like with supplementation and the eye and vision, we see improvements because largely the population across all age ranges is deficient in these carotenoids. When you supplement you’re allowing for accumulation in the eye and that’s related to what’s in your brain and then you see these commensurate improvements.”
The study supports the role for lutein and zeaxanthin throughout the lifespan. “There are studies that characterize roles for lutein and zeaxanthin in the womb, and this is getting passed from the mother to the fetus. And there are roles throughout development. We have data on the amount in infant brains and in centenarian brains. The story is clear: Healthier levels of lutein in the eye and the brain leads to higher cognitive performance.”
Lutein and brain health
The link between lutein and eye health was first reported in 1994 by Dr Johanna Seddon and her co-workers at Harvard University, who found a link between the intake of carotenoid-rich food, particularly dark green leafy vegetables like spinach, and a significant reduction in age-related macular degeneration (AMD) (JAMA, Vol. 272, pp. 1413-1420).
Numerous studies with data from primates, children, middle-aged people, and the elderly now support the importance of lutein in brain health, which is unsurprising given that the eyes and the brain are connected.
Indeed, recent findings from pediatric brain tissue studies have shown that about 60% of the total carotenoids in the pediatric brain tissue is lutein, and yet NHANES data show that lutein is only about 12% of the carotenoids in the diets, so there is a preference for lutein in the brain (Vishwanathan et al. J Pediatr Gastroenterol Nutr. 2014).
A 2017 study by scientists from Queens University Belfast and the Macular Pigment Research Group at the Waterford Institute of Technology found that higher blood levels of lutein and zeaxanthin may be associated with better cognition, memory, and executive function (Journal of Gerontology, Series A).
So, what comes next? Looking ahead, Dr Stringham said elucidating mechanisms of action is a key issue. In their recent study they showed that supplementation with the macular xanthophylls led to increases in both macula pigment optical density (MPOD) – a measure of lutein levels in the eye and brain – and brain-derived neurotrophic factor (BDNF), which has been described as an important neurotrophic factor participating in memory and learning.
“Stepping back a little, I’d like to look at developing eyes and brain in young kids, because we know they especially are not getting enough of these nutrients.”
Dr Stringham's study used Omniactive Health Technologies’ Lutemax 2020 ingredient and the company funded the research.
Source: Physiology & Behavior
November 2019, Volume 211, 112650, doi: 10.1016/j.physbeh.2019.112650
“Effects of macular xanthophyll supplementation on brain-derived neurotrophic factor, pro-inflammatory cytokines, and cognitive performance”
Authors: N.T. Stringham et al.