Improved cognitive performance following supplementation with a mixed-grain diet in high school students: a randomized controlled trial.
OBJECTIVE
Adolescence is a stage of rapid growth, when rich nutritional supplementation is important. Maintaining optimal cognitive functioning is critical in high school students, who are under considerable academic pressure. The objectives of this study were to identify the effects of a 9-wk randomly assigned diet of mixed grains versus a regular diet on cognitive performance and on levels of plasma brain-derived neurotrophic factor (BDNF) and S100B, a calcium-binding protein produced by astroglial cells, in healthy high school students (grades 10 and 11).


METHODS
In this 9-wk, single-blind, controlled study, subjects were randomly allocated to either a mixed-grain or a regular diet. Cognitive assessments and measurements of plasma BDNF and S100B levels were performed at baseline and after the 9-wk intake of a mixed-grain or regular diet. Computerized neuropsychological tests and self-rating scales were used for the cognitive assessments.


RESULTS
Significant improvements in some neuropsychological tests were found after 9 wk in both the mixed-grain and the regular-diet groups, but the changes from baseline between the two groups were not significantly different. Significant impairments on the AX-continuous performance test were observed at the endpoint in the regular-diet group, and the changes from baseline between the two groups were also significantly different for this test. A significant difference in changes in BDNF levels was observed between the two groups.


CONCLUSIONS
These results suggest that intake of mixed grains for 9 wk is beneficial for cognitive performance and plasma BDNF levels in high school students. These beneficial effects seem to be related to the prevention of cognitive deterioration in a mental-fatigue test with the mixed-grain diet, rather than cognitive enhancement per se.
Department of Psychiatry, Chonbuk National University Medical School and Institute for Medical Science, Jeonju, Korea. chungyc@jbnu.ac.kr
Young-Chul
YC
Chung
Chul-Hyun
CH
Park
Hye-Kyung
HK
Kwon
Young-Min
YM
Park
Young Soo
YS
Kim
Jae-Kyun
JK
Doo
Dong-Hwa
DH
Shin
Eun-Soo
ES
Jung
Mi-Ra
MR
Oh
Soo Wan
SW
Chae
D000293:Adolescent; D001921:Brain / Q000378:metabolism*; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism; D003071:Cognition / Q000502:physiology*; D004032:Diet; D019587:Dietary Supplements; D002523:Edible Grain; D006801:Humans; D031324:Juglans; D009483:Neuropsychological Tests; D012275:Oryza; D027805:Phaseolus; D012016:Reference Values; D012639:Seeds; D012647:Self-Assessment; D016037:Single-Blind Method; D013334:Students
D019208:Brain-Derived Neurotrophic Factor; D002135:Calcium-Binding Proteins