Joined: 12/20/2011
Posts: 217
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A Combination of Green Tea Extract and l-Theanine
Improves Memory and Attention in Subjects with Mild Cognitive Impairment: A Double-Blind Placebo-Controlled Study
Journal of Medicinal Food
Published in Volume: 14 Issue 4: March 28, 2011
Abstract
A combination of green tea extract and l-theanine (LGNC-07) has been reported to have beneficial effects on cognition in animal studies.
In this randomized, double-blind, placebo-controlled study, the effect of LGNC-07 on memory and attention in subjects with mild cognitive impairment (MCI) was investigated.
Ninety-one MCI subjects whose Mini Mental State Examination-K (MMSE-K) scores were between 21 and 26 and who were in either stage 2 or 3 on the Global Deterioration Scale were enrolled in this study.
The treatment group (13 men, 32 women; 57.58 ± 9.45 years) took 1,680 mg of LGNC-07, and the placebo group (12 men, 34 women;
56.28 ± 9.92 years) received an equivalent amount of maltodextrin and lactose
for 16 weeks.
Neuropsychological tests (Rey–Kim memory test and Stroop
color–word test) and electroencephalography were conducted to evaluate the
effect of LGNC-07 on memory and attention. Further analyses were stratified by
baseline severity to evaluate treatment response on the degree of impairment
(MMSE-K 21–23 and 24–26).
LGNC-07 led to improvements in memory by marginally
increasing delayed recognition in the Rey–Kim memory test (P = .0572).
Stratified analyses showed that LGNC-07 improved memory and selective attention
by significantly increasing the Rey–Kim memory quotient and word reading in the
subjects with MMSE-K scores of 21–23 (LGNC-07, n = 11; placebo,
n = 9).
Electroencephalograms were recorded in 24 randomly selected
subjects hourly for 3 hours in eye-open, eye-closed, and reading states after a
single dose of LGNC-07 (LGNC-07, n = 12; placebo, n = 12). Brain
theta waves, an indicator of cognitive alertness, were increased significantly
in the temporal, frontal, parietal, and occipital areas after 3 hours in the
eye-open and reading states.
Therefore, this study suggests that LGNC-07 has
potential as an intervention for cognitive improvement.
http://online.liebertpub.com/doi/abs/10.1089/jmf.2009.1374
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According to a commercial website discussing the above study:
"Green tea is used because it contains between 30 and 40 per cent of
water-extractable polyphenols, while black tea and oolong tea contain much less.
The LGNC-07 mix is made up of four primary polyphenols found in fresh tealeaves;
epigallocatechin gallate (EGCG),
epigallocatechin,
epicatechin gallate,
epicatechin,
and the amino acid, L-theanine.
But the benefits of the LGNC-07 cannot be delivered from drinking a
normal cup of tea because the quantity of these agents are too low in
concentration."
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My note: I see that at amazon.com and elsewhere it's easy to buy capsules of green tea extract + L-theanine, though I don't know how their potency compares to what was successful in the above study. And I don't yet know possible side-effects.
Also note that L-Theanine should not be confused with L-Threonate (as in magnesium L-threonate which was discussed on another thread).
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Joined: 12/6/2011
Posts: 3326
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Thanks, onward!
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Joined: 12/12/2011
Posts: 5174
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Thanks, too, Onward. This makes a great deal of sense. An independent researcher on another Alzheimer's website said that when he gave his relative glucuronolactone powder in combination with theanine she became more alert and her behavior improved (the theanine by itself was not particularly effective). A metabolite of glucuronolactone--glucaric acid--is found in apple juice (although the sugar in the juice may be somewhat of a problem). Apple juice like green tea has been suggested as a way to delay the onset of Alzheimer's disease and as a possible treatment for Alzheimer's disease especially during its early stages.
http://www.eurekalert.org/pub_releases/2009-01/ip-nsp012209.php
http://www.ncbi.nlm.nih.gov/pubmed/20338990
The key to treating Alzheimer's disease appears to be the donation of hydrogen atoms. Green tea polyphenols contain multiple hydroxyl groups (OH) which are excellent hydrogen donors and may both delay the onset of Alzheimer's disease and potentially can be used to treat the disease. Other compounds containing only one hydroxyl group can also be beneficial as well as long as they have at least one other hydrogen atom to donate (a methyl group--CH3 or certain amino acids possibly including theanine).
I think decaffeinated green tea would work best with few if any side effects (for some individuals taking a blood thinner, green tea extracts or drinking lots of green tea may pose a problem). In general, though, green tea should be safe. Theanine is also generally considered to be safe.
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Joined: 12/12/2011
Posts: 5174
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In a way these two articles have nothing and everything to do with green tea, theanine, and Alzheimer's disease.
http://www.ncbi.nlm.nih.gov/pubmed/22142544
http://www.ncbi.nlm.nih.gov/pubmed/11259863
It's just a matter of which hydrogen donors readily enter the brain and which are the best peroxynitrite scavengers.
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Joined: 12/20/2011
Posts: 217
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Thanks for all that additional info, Lane.
So... you think decaffeinated green tea (or extract) would be just as helpful as green tea with caffeine? As you know, many people want to avoid caffeine.
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Joined: 12/12/2011
Posts: 5174
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The answer to the question of whether decaffeinated green tea is just as effective as caffeinated green tea turns out to be more complicated than I expected. I like decaffeinated teas in general because they have fewer side effects than caffeinated teas. Although there have been studies indicating that caffeine may provide some protection against Alzheimer's disease, the most beneficial aspects of tea and coffee are provided by polyphenols. However, some polyphenols are lost in the decaffeination process (apparently the carbon dioxide extraction method, which is not widely used, retains most of the polyphenols). So I suppose if a person tolerates caffeine well that is the best option. Otherwise, some benefit may still be obtained from decaffeinated green tea.
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Joined: 12/20/2011
Posts: 217
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Can anyone help me find out whether the exact formula of "LGNC-07" that was shown to improve memory is a product available for purchase?
So far, I've only seen the study abstract available free online, and can't locate the full paper. But I did find some articles discussing the study. Here are some of the details they give:
"LGNC-07 is a 6:1 ratio of green tea catechins to theanine, with 360mg catechins and 60mg theanine per 430mg capsule."
http://examine.com/supplements/Green+Tea+Catechins/#summary11-2
"The treatment group... took 1,680 mg of LGNC-07... for 16 weeks"
http://www.ncbi.nlm.nih.gov/pubmed/21303262
"Subjects were randomized into either treatment or placebo groups. All took two 430 mg capsules twice a day 30 minutes before eating for 16 weeks. The treatment capsules consisted of 360 mg of green tea extract and 60 mg of l-theanine, or a daily dose of 1,440 mg green tea extract per day and 240 mg of l-theanine. The strength of the green tea extract is not specified in the study."
http://denvernaturopathic.com/l-theanineandAlzheimers.htm
"The subjects... were instructed to take two 430 mg capsules of treatment or placebo twice daily 30 minutes after meals for 16 weeks.
"Treatment capsules contained 360 mg of green tea extract, 60 mg of l-theanine, 5.7 mg of silicon dioxide, and 4.3 mg of magnesium stearate. No further information regarding LGNC-07 was provided in the article."
http://cms.herbalgram.org/herbclip/428/031132-428.html
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Joined: 12/12/2011
Posts: 5174
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I am not certain of this, but it appears that the same company (LG Household and Health Care Ltd.) that sponsored the study also produces the extract.
Here is there contact information.
http://www.gobizkorea.com/blog/index.do?blogId=lgcare
If you have success in tracking down LGNC-70, Onward, let us know.
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Joined: 12/20/2011
Posts: 217
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Good detective work, Lane. You're right.
http://www.nutraingredients-usa.com/Research/Green-tea-extract-shows-memory-boosting-activity-Study
(I still haven't located the exact product though.)
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Joined: 12/12/2011
Posts: 5174
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Even better research on your part, Onward. Now we know for sure what company produces LGNC-70. I hope that it is not too hard to get a hold of.
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