Scientists from the Waterford Institute of Technology’s (WIT) world-renowned Macular Pigment Research Group (MPRG) report that a significant association was observed between macular pigment levels in the eye and various measures of cognitive performance in 105 people with low macular pigment (MP) and 121 people with early age-related macular degeneration.
“[I]t is reasonable to hypothesize that MP is a valid biomarker for cognitive function, and its role in this regard warrants further exploration for the wider population,” they wrote in the Journal of Alzheimer’s Disease.
“[T]he possibility that supplementation with MP’s constituent carotenoids may delay the onset or ameliorate the progression of cognitive decline cannot be ignored.”
Supplementation with lutein, zeaxanthin and meso-zeaxanthin
The Macular Pigment Research Group also conducted a randomized clinical trial with patients with Alzheimer’s disease and supplementation with lutein, zeaxanthin and meso-zeaxanthin, also published in the Journal of Alzheimer’s Disease. The trial was performed in collaboration with the University Hospital Waterford and the Howard Foundation.
“What our research has found is that patients with Alzheimer’s disease not only have lower cognition but also considerably poorer vision compared to their peers of the same age without Alzheimer’s,” said Prof John Nolan, principal investigator at the MPRG.
“Furthermore, we have found that those with Alzheimer’s are significantly lacking in lutein, zeaxanthin and meso-zeaxanthin. These nutrients are known as dietary carotenoids and at the back of the eye where they are vitally important, they are referred to as macular pigment.
“Stepping on from this finding, we were keen to establish whether it was possible to help restore some of the vision that has been lost in those with Alzheimer’s. Our trials using supplements that are rich in carotenoids found that patients did indeed experience improved vision as their macular pigment was boosted.”
Lutein and brain health
Other research groups around the world are also pursuing this avenue of research with a published paper by Billy Hammond’s group at the University of Georgia (Neurobiology of Aging, 2014, Vol. 35, pp. 1695-9) reporting that MPOD was related to general cognition in people with mild cognitive impairment (MCI), while MPOD was only related to visual-spatial and constructional abilities in healthy older adults.
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).
Cognitive Health Online Summit
Experts from Abbott Nutrition, GOED, Nordic Naturals, The University of Toronto, McMaster University, and NutraIngredients-USA will discuss a range of cognitive health topics during NutraIngredients-USA’s Cognitive Health Online Summit.
The online event will take place on September 2, 2015. For more information and to register, please click here: NutraIngredients-USA’s Cognitive Health Online Summit.
Sources: Journal of Alzheimer’s Disease
Volume 48, Number 1, doi: 10.3233/JAD-150199
“Cognitive Function and Its Relationship with Macular Pigment Optical Density and Serum Concentrations of its Constituent Carotenoids”
Authors: D. Kelly, R.F. Coen, K. Owusu Akuffo, et al.
Journal of Alzheimer’s Disease
Volume 44, Pages 1157–1169, doi: 10.3233/JAD-142265
“The Impact of Supplemental Macular Carotenoids in Alzheimer’s Disease: A Randomized Clinical Trial”
Authors: J.M. Nolan, E. Loskutova, A. Howard, et al.