The combination of green tea extract and L-theanine (LGNC-07) has been reported to have cognition improving effect in animal studies(Reference Kim, Yuk and Park1). In this randomized, double-blinded placebo-controlled study, we investigated the effect of LGNC-07 on memory and attention in the mild cognition impaired (MCI) subjects(Reference Petersen, Doody and Kurz2). Ninety-one MCI subjects whose MMSE-K scores were between 21 and 26 with 2–3 stages of GDS were enrolled in this study. The treatment group (13 males, 32 females; 57.58±9.45 years) took 1440 mg GTE and 240 mg L-theanine and the placebo group (12 males, 34 females; 56.28±9.92 years) took the equivalent amount of maltodextrin and lactose for 16 weeks. Rey–Kim memory test, Stroop colour-word test were conducted to evaluate the effect of LGNC-07 on memory and selective attention.
Data are represented as the differences from baseline in stratified subjects.
a Means denote significance between placebo and treatment by Wilcoxon rank sum test; P<0.05.
b Means denote significant increase after treatment by paired sample t-test; P<0.05.
LGNC-07 showed memory improvement by marginally increasing the delayed recognition of Rey–Kim memory test (P=0.0572) and especially it significantly increases Rey–Kim MQ in stratified subjects (LGNC-07, n 11; placebo, n 9) whose MMSE-K lies between 21 and 23 (P<0.05). Selective attention was also improved in the stratified subjects bya significant increase of word reading (P<0.05). Therefore, this study suggests that LGNC-07 might be a potential nutraceutical candidate for cognition improvement.