Rebecca Power1, Robert F Coen2, Stephen Beatty1, Riona Mulcahy3, Rachel Moran1, Jim Stack1, Alan N Howard4, John M Nolan1. 1. Nutrition Research Centre Ireland, School of Health Science, Carriganore House, Waterford Institute of Technology, West Campus, Waterford, Ireland. 2. Mercer's Institute for Research on Ageing, St. James's Hospital, Dublin, Ireland. 3. Age-related Care Unit, University Hospital Waterford, Waterford, Ireland. 4. Howard Foundation, Cambridge, UK.
Abstract
BACKGROUND: There is a biologically plausible rationale whereby the dietary carotenoids lutein (L), zeaxanthin (Z), and meso-zeaxanthin (MZ), which are collectively referred to as macular pigment (MP) in the central retina (macula), support the maintenance of cognition via their antioxidant and anti-inflammatory properties. OBJECTIVE: To investigate the impact of supplemental L, Z, and MZ on memory, executive function, and verbal fluency among healthy individuals with low MP levels. METHODS: In this double-blind, placebo-controlled, randomized clinical trial, subjects (n = 91; mean±SD age = 45.42±12.40; % male = 51.6) consumed a daily formulation of 10 mg L, 10 mg MZ, and 2 mg Z (n = 45) or placebo (n = 46) for 12 months. Cognitive domains assessed included verbal and visual learning, immediate and delayed memory, executive function, and verbal fluency. MP and serum carotenoid concentrations of L, Z, and MZ were also measured. RESULTS: Following 12-month supplementation, individuals in the active group exhibited statistically significant improvements in memory when compared to the placebo group (paired associated learning [PAL] memory score [rANOVA, p = 0.009]; PAL errors [rANOVA, p = 0.017]). Furthermore, the observed reduction in the number of errors made in the PAL task among those in the intervention group was positively and significantly related to observed increases in MP volume (p = 0.005) and observed increases in serum concentrations of L (p = 0.009). CONCLUSION: This randomized, double-blind, placebo-controlled clinical trial demonstrates a memory-enhancing effect of daily supplementation with L, Z, and MZ in healthy subjects with low MP at baseline. The implications of these findings for intellectual performance throughout life, and for risk of cognitive decline in later life, warrant further study.
RCT Entities:
BACKGROUND: There is a biologically plausible rationale whereby the dietary carotenoids lutein (L), zeaxanthin (Z), and meso-zeaxanthin (MZ), which are collectively referred to as macular pigment (MP) in the central retina (macula), support the maintenance of cognition via their antioxidant and anti-inflammatory properties. OBJECTIVE: To investigate the impact of supplemental L, Z, and MZ on memory, executive function, and verbal fluency among healthy individuals with low MP levels. METHODS: In this double-blind, placebo-controlled, randomized clinical trial, subjects (n = 91; mean±SD age = 45.42±12.40; % male = 51.6) consumed a daily formulation of 10 mg L, 10 mg MZ, and 2 mg Z (n = 45) or placebo (n = 46) for 12 months. Cognitive domains assessed included verbal and visual learning, immediate and delayed memory, executive function, and verbal fluency. MP and serum carotenoid concentrations of L, Z, and MZ were also measured. RESULTS: Following 12-month supplementation, individuals in the active group exhibited statistically significant improvements in memory when compared to the placebo group (paired associated learning [PAL] memory score [rANOVA, p = 0.009]; PAL errors [rANOVA, p = 0.017]). Furthermore, the observed reduction in the number of errors made in the PAL task among those in the intervention group was positively and significantly related to observed increases in MP volume (p = 0.005) and observed increases in serum concentrations of L (p = 0.009). CONCLUSION: This randomized, double-blind, placebo-controlled clinical trial demonstrates a memory-enhancing effect of daily supplementation with L, Z, and MZ in healthy subjects with low MP at baseline. The implications of these findings for intellectual performance throughout life, and for risk of cognitive decline in later life, warrant further study.
Authors: Sookyoung Jeon; Qiyao Li; Stanislav S Rubakhin; Jonathan V Sweedler; Joshua W Smith; Martha Neuringer; Matthew Kuchan; John W Erdman Journal: Nutr Res Date: 2018-10-28 Impact factor: 3.315
Authors: Anna Piovan; Raffaella Filippini; Giovanni Corbioli; Vanessa Dalla Costa; Elisabetta Maria Vittoria Giunco; Gianluca Burbello; Andrea Pagetta; Pietro Giusti; Morena Zusso Journal: Mol Neurobiol Date: 2021-03-21 Impact factor: 5.590
Authors: Regan L Bailey; Tieraona Low Dog; Abbie E Smith-Ryan; Sai Krupa Das; Fiona C Baker; Zeynep Madak-Erdogan; Billy R Hammond; Howard D Sesso; Alex Eapen; Susan H Mitmesser; Andrea Wong; Haiuyen Nguyen Journal: J Nutr Date: 2022-07-06 Impact factor: 4.687
Authors: Naiman A Khan; Anne M Walk; Caitlyn G Edwards; Alicia R Jones; Corinne N Cannavale; Sharon V Thompson; Ginger E Reeser; Hannah D Holscher Journal: Nutrients Date: 2018-03-23 Impact factor: 5.717
Authors: Fábio B Daga; Nara G Ogata; Felipe A Medeiros; Rachel Moran; Jeffrey Morris; Linda M Zangwill; Robert N Weinreb; John M Nolan Journal: Invest Ophthalmol Vis Sci Date: 2018-09-04 Impact factor: 4.799
Authors: Marina Green-Gomez; Paul S Bernstein; Christine A Curcio; Rachel Moran; Warren Roche; John M Nolan Journal: Transl Vis Sci Technol Date: 2019-12-18 Impact factor: 3.283
Authors: Catherine M Mewborn; Cutter A Lindbergh; Talia L Robinson; Marissa A Gogniat; Douglas P Terry; Kharine R Jean; Billy Randy Hammond; Lisa M Renzi-Hammond; Lloyd Stephen Miller Journal: Nutrients Date: 2018-04-07 Impact factor: 5.717