@article{afc93f4ef58143268a69f4f2a31703ff,
title = "Effects of lutein and astaxanthin intake on the improvement of cognitive functions among healthy adults: A systematic review of randomized controlled trials",
abstract = "Background: Fruits and vegetables are generally rich in antioxidants such as carotenoids. Consumption of carotenoids is expected to have benefits on cognitive functions in humans. However, previous randomized controlled trials (RCT) using carotenoids have reported inconsistent results. Therefore, this systematic review (SR) aimed to summarize the effect of carotenoid intake on cognitive functions in humans. Method: PubMed, Cochrane Library, Web of Science, and PsychoINFO were searched for research papers on carotenoid intake with the criteria that 1) oral carotenoid intake was evaluated using RCTs, 2) participants were healthy young, middle-aged, or older, and 3) cognitive functions were measured using RCTs. Results: Five studies using lutein and two studies using astaxanthin met the inclusion criteria. Consumption of lutein and its isomer showed consistent results in selective improvement of visual episodic memory in young and middle-aged adults while inhibition was observed in middle-aged and older adults. One of the two included astaxanthin studies reported a significant improvement of verbal episodic memory performance in middle-aged adults. Conclusion: This SR showed that the 10 mg lutein per day for twelve months can lead to improvement of cognitive functions. Due to the small number of studies, it is difficult to conclude whether astaxanthin would have a positive effect on cognitive functions.",
keywords = "Astaxanthin, Carotenoids, Episodic memory, Inhibition, Intervention, Lutein",
author = "Rui Nouchi and Takahiko Suiko and Eriko Kimura and Hiroki Takenaka and Michiaki Murakoshi and Akira Uchiyama and Megumi Aono and Ryuta Kawashima",
note = "Funding Information: Conflicts of Interest: This study was a corroborative study between Institute of Development, Aging, and Cancer (IDAC), Tohoku University and Lion Corporation. supported by Lion Corporation. R.N and R.K received research grants from Lion Corporation. T.S., E.K, H.T., M.M., A.U., and M.A are full-time employees of Lion Corporation. The company policy was not involved in the study design, collection, analysis, interpretation of data, or writing of the manuscript. The authors declare that they have no other competing interests. Funding Information: Power, 2018 was funded by the European Research Council. Lindberg 2018 was funded in part by Abbott Nutritional Products and the University of Georgia{\textquoteright}s Bio-Imaging Research Center. Johnson 2008 was supported by USDA 1950-5100-065, Mead Johnson Nutritionals, and Martek Biosciences Corporation. Katagiri 2012 was supported by a grant from Yamaha Motors Co., Ltd. Two authors (M.H. and T.I.) of Hayashi 2018 were employees of JXTG Nippon Oil & Energy Corporation. Additionally, three studies were supported by Abbott Nutrition and used intervention supplements supplied by DSM Nutritional Products [21,29,32]. Funding Information: Funding: This study is also supported by JSPS KAKENHI Grant Number 16KT0002, 19H01760 (Grant-in-Aid for Scientific Research (B) and 19H05003 (Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)). None of the funding sources had any involvement in the study design, collection, analysis, interpretation of data, or the writing of the paper. Publisher Copyright: {\textcopyright} 2020 by the authors. Licensee MDPI, Basel, Switzerland.",
year = "2020",
month = mar,
doi = "10.3390/nu12030617",
language = "English",
volume = "12",
journal = "Nutrients",
issn = "2072-6643",
publisher = "Multidisciplinary Digital Publishing Institute (MDPI)",
number = "3",
}