Hi,
i dont come along very well with caffeine so i am looking for teas that contain less.
Unfortunately i get digestion-problems from japanese greens, so bancha falls apart.
Which else green teas i could give a try??
Whats about oolong??
Imi
Have you tried Kukicha or Houjicha? Are you sure that you get digestion problems from all Japanese greens?
I do not know of any not-Japanese greens that are extraordinary low in caffeine.
Stay away from Matcha and Gyokuro!
Oolong is not a green tea per se but there are green oolong. Oolong has more caffeine than the average green tea it seems, although not as much as a black tea.
You could always go for herbals. Rooibos, Honeybush, Hibiscus, Chamomille, Mint...
I do not know of any not-Japanese greens that are extraordinary low in caffeine.
Stay away from Matcha and Gyokuro!
Oolong is not a green tea per se but there are green oolong. Oolong has more caffeine than the average green tea it seems, although not as much as a black tea.
You could always go for herbals. Rooibos, Honeybush, Hibiscus, Chamomille, Mint...
The noise comes from the other side of the mirror
You will probably have better luck with Chinese Greens, if you are looking
for a green tea, There is much debate over health benefits between the teas.
If you eliminate Japanese greens, then the rest on on a pretty level playing field.
Drink what you like - that way you will enjoy it and drink more of it.
Oolongs are great, my favorites. Try some Chinese greens,
give whites a try too.
for a green tea, There is much debate over health benefits between the teas.
If you eliminate Japanese greens, then the rest on on a pretty level playing field.
Drink what you like - that way you will enjoy it and drink more of it.
Oolongs are great, my favorites. Try some Chinese greens,
give whites a try too.
- Victoria -
http://victoriasown.blogspot.com/
http://victoriasown.blogspot.com/
If you do gong fu cha preparing method, you flush off the tea for a few seconds, that removes a bit of coffein, but you cannot do this with green tea, you might loose precious flavour, generally matcha koicha has the strongest effect, over 6 hours of stimulation, after that comes gyokuro, and sencha, and generally chinese green tea has less coffein, but the ULTIMAT COFFEIN LOW TEA IS WHITE TEA, you can drink it almost all of the time without having to worrie about coffein it has the least amount from all teas and tastes similar too green tea because the lack of fermentation.
Mar 10th, '09, 17:40
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silverneedles
there's lots of talk on caffeine on this website
http://www.google.com/search?&num=100&q ... 3Acaffeine
you cant say which tea is low or high in caffeine green/white/oolong
also a good read:
A Decent DeCaf Green - Is There Such A Thing?
http://groups.google.com/group/rec.food ... 4a1085cedf#
http://www.google.com/search?&num=100&q ... 3Acaffeine
you cant say which tea is low or high in caffeine green/white/oolong
also a good read:
A Decent DeCaf Green - Is There Such A Thing?
http://groups.google.com/group/rec.food ... 4a1085cedf#
It's the shade, man.
Select Japanese tea leaves are shaded, for a period of several weeks before plucking.
Sun converts theanine in youngest tea leaves to polyphenols - natural sunscreen agents that protect these leaves against sunburn effects.
Japanese tea growers seek to limit polyphenol bitterness in tea cultivars that have naturally high levels of theanine. Shading reduces polyphenols, but also theanine content, too.
Theanine counterbalances stimulatory effect on nerve cells. Theanine is chemically similar to glutamate and glutamine, but where glutamate excites nerve cells, theanine blocks this action, inhibiting their excitation, 'calming' them.
Stomach acid effectors are nerve-type cells that respond to stimulus of excitation and inhibition. Caffeine is one excitatory agent. But there are others in tea that are simple nitrogen-rich amino acids: arginine and glutamine.
Arginine and alanine are specifically made in the roots of tea plants in India and Japan, but not China - a function of the cultivars and growing conditions (fertilizers used).
Arginine is converted into glutamine. Glutamate excites stomach acid receptors, and its more pronounced in those who have a diet high in glutamate-containing foods, because you can develop a 'trigger finger' effect in these nerve cells from excessive stimulation.
Alanine, another important nitrogen-cycle amino acid, is also excitatory actor on NMDA (glutamate related) nerve receptors in secretory organs (spleen, pancreas, gallbladder, stomach, and indirectly, kidney and liver).
Green teas can have higher levels of excitatory agents than you would expect (the point that SN is trying to make). But the whole story doesn't rest with caffeine. It also includes the amino content of certain teas.
Shading may help counter polyphenol production, and hence bitterness, but it comes with a price. It reduces the natural counter to caffeine and glutamine (converted to glutamate in stomach acid)
For science nerds:
Transport of Nitrogen Assimilation in Xylem Vessels of Green Tea Plants Fed with NH4-N and NO3-N. K. OHa, T. KATO and H.L. XU Center for Environmental Science in Saitama, Saitama Japan and International Nature Farming Research Center, 5632 Hata, Nagano Japan. February 2008.
An experiment was carried out to study the transport process of nitrogen (N) assimilation from tea roots by monitoring the dynamic composition of N compounds in xylem sap after 15N-NO3 and 15N-NH4 were fed to the root of tea plants (Camellia sinensis L.). Results showed that the main amino acids were glutamine, theanine, arginine, asparic acid and glutamic acid, which accounted for 49%, 17%, 8%, 7%, and 4%, respectively, of the total amino acids in the xylem sap. After the tea plants were fed with 15N-NO3 and 15N-NH4 for 48 h, the amount of total amino acids in xylem sap significantly increased and those fed with 15N-NH4 had higher increment than those with 15N-NO3. Two hours after 15N- NO3 and 15N-NH4 were fed, 15N abundance in glutamine, asparagine, glutamic acid, alanine, and arginine were detected and increased quickly over time. This indicated that it took less than 2 h for NO3-N and NH4-N to be absorbed by tea roots, incorporated into the above amino acids and transported to the xylem sap. Rapid increase in 15N-NO3 in the xylem sap of tea plants fed with 15N-NO3 indicated that nitrate could be directly transported to the xylem sap. Glutamine, theanine, and alanine were the main amino acids transported in xylem sap of tea plants fed with both 15N-NO3 and 15N-NH4.
See also:
rms1.agsearch.agropedia.affrc.go.jp/contents/JASI/pdf/digicon/rreport/report/nivot/nivot1979-tgk56-7.pdf
Glutamine synthase activity, and its relationship to stress levels, heavy metals and nitrate in tea plants:
Expression of tea cytosolic glutamine synthetase is tissue specific and induced by cadmium and salt stress. N. K. Rana, P. Mohanpuria and S. K. Yadav. Biotechnology Division, Institute of Himalayan Bioresource Technology (CSIR), Palampur, 176061, India June 2008.
Sun converts theanine in youngest tea leaves to polyphenols - natural sunscreen agents that protect these leaves against sunburn effects.
Japanese tea growers seek to limit polyphenol bitterness in tea cultivars that have naturally high levels of theanine. Shading reduces polyphenols, but also theanine content, too.
Theanine counterbalances stimulatory effect on nerve cells. Theanine is chemically similar to glutamate and glutamine, but where glutamate excites nerve cells, theanine blocks this action, inhibiting their excitation, 'calming' them.
Stomach acid effectors are nerve-type cells that respond to stimulus of excitation and inhibition. Caffeine is one excitatory agent. But there are others in tea that are simple nitrogen-rich amino acids: arginine and glutamine.
Arginine and alanine are specifically made in the roots of tea plants in India and Japan, but not China - a function of the cultivars and growing conditions (fertilizers used).
Arginine is converted into glutamine. Glutamate excites stomach acid receptors, and its more pronounced in those who have a diet high in glutamate-containing foods, because you can develop a 'trigger finger' effect in these nerve cells from excessive stimulation.
Alanine, another important nitrogen-cycle amino acid, is also excitatory actor on NMDA (glutamate related) nerve receptors in secretory organs (spleen, pancreas, gallbladder, stomach, and indirectly, kidney and liver).
Green teas can have higher levels of excitatory agents than you would expect (the point that SN is trying to make). But the whole story doesn't rest with caffeine. It also includes the amino content of certain teas.
Shading may help counter polyphenol production, and hence bitterness, but it comes with a price. It reduces the natural counter to caffeine and glutamine (converted to glutamate in stomach acid)
For science nerds:
Transport of Nitrogen Assimilation in Xylem Vessels of Green Tea Plants Fed with NH4-N and NO3-N. K. OHa, T. KATO and H.L. XU Center for Environmental Science in Saitama, Saitama Japan and International Nature Farming Research Center, 5632 Hata, Nagano Japan. February 2008.
An experiment was carried out to study the transport process of nitrogen (N) assimilation from tea roots by monitoring the dynamic composition of N compounds in xylem sap after 15N-NO3 and 15N-NH4 were fed to the root of tea plants (Camellia sinensis L.). Results showed that the main amino acids were glutamine, theanine, arginine, asparic acid and glutamic acid, which accounted for 49%, 17%, 8%, 7%, and 4%, respectively, of the total amino acids in the xylem sap. After the tea plants were fed with 15N-NO3 and 15N-NH4 for 48 h, the amount of total amino acids in xylem sap significantly increased and those fed with 15N-NH4 had higher increment than those with 15N-NO3. Two hours after 15N- NO3 and 15N-NH4 were fed, 15N abundance in glutamine, asparagine, glutamic acid, alanine, and arginine were detected and increased quickly over time. This indicated that it took less than 2 h for NO3-N and NH4-N to be absorbed by tea roots, incorporated into the above amino acids and transported to the xylem sap. Rapid increase in 15N-NO3 in the xylem sap of tea plants fed with 15N-NO3 indicated that nitrate could be directly transported to the xylem sap. Glutamine, theanine, and alanine were the main amino acids transported in xylem sap of tea plants fed with both 15N-NO3 and 15N-NH4.
See also:
rms1.agsearch.agropedia.affrc.go.jp/contents/JASI/pdf/digicon/rreport/report/nivot/nivot1979-tgk56-7.pdf
Glutamine synthase activity, and its relationship to stress levels, heavy metals and nitrate in tea plants:
Expression of tea cytosolic glutamine synthetase is tissue specific and induced by cadmium and salt stress. N. K. Rana, P. Mohanpuria and S. K. Yadav. Biotechnology Division, Institute of Himalayan Bioresource Technology (CSIR), Palampur, 176061, India June 2008.
Intuit, I'm confused. You said that sun converts theanine to polyphenols. Therefore shaded teas should have the highest theanine and thus the highest level of agents which counteract the stimulatory effects of caffeine. However you said
http://en.wikipedia.org/wiki/Theanine
Let me know if I'm missing something or if i simply read your statement wrong.
While I specialize more in humans than plants, feel free to give me a nice scientific answer if you're inclined. Thanks!
This is also what I saw on the wikipedia article which led me to believe that gyokuro had one of the highest theanine levels. It is my understanding that theanine would not counteract the irritable nature of caffeine to the stomach (caffeine increases parietal cell activity and thus greater acid secretion in the stomach), but rather theanine is suspected to be largely a psychoactive agent.Shading may help counter polyphenol production, and hence bitterness, but it comes with a price. It reduces the natural counter to caffeine and glutamine (converted to glutamate in stomach acid)
http://en.wikipedia.org/wiki/Theanine
Let me know if I'm missing something or if i simply read your statement wrong.
While I specialize more in humans than plants, feel free to give me a nice scientific answer if you're inclined. Thanks!
There has been a saying whiteness of leaf is due to high content of amino acid, such as An Ji Bai Cha, Bai Ji Guan or legendary 'Bai Cha' Song emperor Huizong enjoyed himself, those teas are pronounced with a sweet lingering on tongue.
I don't know if it's due to caffeine, but I listen to my pee-reactive time
and body reaction.
When drinking Black, I often witness my body cooled off quickly, and pee quick.
When drinking Wuyi, I feel my body warmed up and pee late.
somethin like that..
I don't know if it's due to caffeine, but I listen to my pee-reactive time
and body reaction.When drinking Black, I often witness my body cooled off quickly, and pee quick.
When drinking Wuyi, I feel my body warmed up and pee late.
somethin like that..
In tea plants: glutamate is converted to theanine, and theanine is used to build polyphenols. Shading preserves theanine (keeps it from being converted to catechins), but there is also an effect of fertilizer nitrogen on buildup of glutamate used to make theanine (and related N-cycle components, arginine and alanine).
www.thorne.com/media/mono_theanine10-2.pdf
Monosodium glutamate increases histamine-induced gastric acid secretion with time.
Monosodium Glutamate, a Possible Threat to Gastric Integrity in Rat.pdf JBC (Asian) 6(4):671-674 (2006).
GABA hydrophobic structural analog also appear to modulate gastric acid release:
Antiulcer and gastric secretory activity of N-octanoyl γ- aminobutyric acid. Suchandra Sen, Mohammed Habibuddin and Sankar Prasad Pal. Life Sci.
57(20):1877-1885 (1995).
A new γ-aminobutyric acid derivative synthesised in this laboratory, N-octanoyl γ-aminobutyric acid was found to possess antinociceptive activity but no anticonvulsant activity. The effect of the compound on gastric lesions produced by aspirin, ethanol and stress in rats, was studied and the compound was found to possess effective antiulcer action. Even though, N-octanoyl γ-aminobutyric acid did not produce a significant change in the volume of gastric acid secretion, however, it decreased the acidity and peptic activity and significantly enhanced the gastric mucus secretion.
(see the related newer paper below on nocioreceptor action on gastric secretion)
Luminal amino acid sensing in the rat gastric mucosa. Hisayuki Uneyama, Akira Niijima, Ana San Gabriel, and Kunio Torii. Am J Physiol Gastrointest Liver Physiol 291: G1163-G1170, 2006.
The role of ionotropic glutamate receptors ampa/kainate type
in the mechanism of formation of basal gastric acid secretion in rats. T. FALALYEYEVA, L. SHTANOVA, T. DRYVECKA, T. BEREGOVA. Anals. Univ. Marie Curie - S K Łodowwska Lublin-Poland. XX:N 1,7 Sect DDD (2007).
Basal or interdigestive gastric acid secretion (GAS) is singularity for most mammal. It is known that basal GAS is caused by tonic activity of nerve vagus. But it was established that basal GAS is reduced but not abolished by vagotomy [3]. Most probably, there exist other mechanisms of occurrence of basal GAS. Such as glutamate is the major excitatory neurotransmitter in the central
nervous system (CNS) we supposed that it can take part in the mechanism of formation of basal GAS. Glutamate acts via the activation of ionotropic (N-methyl-D-aspartate [NMDA], [AMPA (α-amino-3-hydroxy-5-methyl-4-isoxaz olepropionic acid)]/kainate) and metabotropic receptors (mGlur group I, II and III).
>>It is known that ionotropic glutamate receptor systems are involved in the central stimulation of gastric acid secretion,
because central (into the lateral cerebroventricule, nucleus raphe pallidus, nucleus raphe obscurus) injection of kainate and NMDA stimulated GAS [4, 9, 10]. But kainate bilaterally microinjected into the arcuate nucleus induced an inhibition of pentagastrin stimulated GAS [6]. Also, it was reported that L-Glutamate injected intravenously had no effect on basal GAS [7, 8].
Ionotropic glutamate receptors are also present in the peripheral neurons of gastrointestinal tract [5]. In our work we test the hypothesis that glutamate, the major excitatory neurotransmitter of the CNS, is also an excitatory neurotransmitter in the enteric nervous system. Therefore, we investigated the influence of antagonist of AMPA/kainate receptors IEM 1751 on basal GAS in rats with intact nervous system and after the bilateral vagotomy.
There is evidence of Glutamate/GABA acting on pain-sensing system (vallinoid receptors).
Capsaicin- and anandamide-induced gastric acid secretion via vanilloid receptor type 1 (TRPV1) in rat brain. Sachie Minowa, Satomi Ishihara, Shizuko Tsuchiya, Syunji Horie and Toshihiko Murayama. Chemical Pharmacology, School of Pharmaceutical Sciences, Chiba University, Japan. Brain Research 1039 (1-2):75-83 (2005).
The activation of transient receptor potential vanilloid receptor 1 (TRPV1) by capsaicin in rat brain stimulates gastric acid secretion via tachykinin NK2 receptors and the vagus cholinergic nerve, but the involvement of other receptor systems has not been elucidated. We investigated the role of the glutamate and γ-amino-butyric acid (GABA) receptor systems on the capsaicin response. Gastric acid secretion stimulated by the injection of capsaicin (30 nmol) into the lateral cerebroventricle (i.c.v.) was inhibited by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, an antagonist of non-N-methyl-d-aspartate (non-NMDA) receptors, 10.9 nmol, i.c.v.) and bicuculline (a GABAA receptor antagonist, 222 μg kg−1 10 min−1, i.v. infusion). Secretion stimulated by the injection of capsaicin (50 nmol) into the fourth cerebroventricle was inhibited by CNQX and bicuculline. I.c.v. injection of anandamide (an endogenous ligand of TRPV1 and cannabinoid receptors, 30 and 100 nmol) stimulated gastric acid secretion, and the response was inhibited by an antagonist of TRPV1 and in the capsaicin-treated rats, but not by an antagonist of cannabinoid receptors. In conclusion, the TRPV1 system, which is activated by capsaicin and anandamide, is preferentially coupled with non-NMDA and GABAA receptor systems in the brain and stimulates gastric acid secretion in rats.
Chrl42 astutely notes:
"I don't know if it's due to caffeine, but I listen to my pee-reactive time Cool and body reaction.
When drinking Black, I often witness my body cooled off quickly, and pee quick.
When drinking Wuyi, I feel my body warmed up and pee late.
Cooling off = glutamate clamping of NO in peripheral circulatory tract, that is vasoconstriction that results in reduced blood flow and 'cooling' effect, in the absence of theanine which counters glutamate effect on vascular system.
Peeing = brain (epinephrine) release temporarily increases urine production.
www.thorne.com/media/mono_theanine10-2.pdf
Monosodium glutamate increases histamine-induced gastric acid secretion with time.
Monosodium Glutamate, a Possible Threat to Gastric Integrity in Rat.pdf JBC (Asian) 6(4):671-674 (2006).
GABA hydrophobic structural analog also appear to modulate gastric acid release:
Antiulcer and gastric secretory activity of N-octanoyl γ- aminobutyric acid. Suchandra Sen, Mohammed Habibuddin and Sankar Prasad Pal. Life Sci.
57(20):1877-1885 (1995).
A new γ-aminobutyric acid derivative synthesised in this laboratory, N-octanoyl γ-aminobutyric acid was found to possess antinociceptive activity but no anticonvulsant activity. The effect of the compound on gastric lesions produced by aspirin, ethanol and stress in rats, was studied and the compound was found to possess effective antiulcer action. Even though, N-octanoyl γ-aminobutyric acid did not produce a significant change in the volume of gastric acid secretion, however, it decreased the acidity and peptic activity and significantly enhanced the gastric mucus secretion.
(see the related newer paper below on nocioreceptor action on gastric secretion)
Luminal amino acid sensing in the rat gastric mucosa. Hisayuki Uneyama, Akira Niijima, Ana San Gabriel, and Kunio Torii. Am J Physiol Gastrointest Liver Physiol 291: G1163-G1170, 2006.
The role of ionotropic glutamate receptors ampa/kainate type
in the mechanism of formation of basal gastric acid secretion in rats. T. FALALYEYEVA, L. SHTANOVA, T. DRYVECKA, T. BEREGOVA. Anals. Univ. Marie Curie - S K Łodowwska Lublin-Poland. XX:N 1,7 Sect DDD (2007).
Basal or interdigestive gastric acid secretion (GAS) is singularity for most mammal. It is known that basal GAS is caused by tonic activity of nerve vagus. But it was established that basal GAS is reduced but not abolished by vagotomy [3]. Most probably, there exist other mechanisms of occurrence of basal GAS. Such as glutamate is the major excitatory neurotransmitter in the central
nervous system (CNS) we supposed that it can take part in the mechanism of formation of basal GAS. Glutamate acts via the activation of ionotropic (N-methyl-D-aspartate [NMDA], [AMPA (α-amino-3-hydroxy-5-methyl-4-isoxaz olepropionic acid)]/kainate) and metabotropic receptors (mGlur group I, II and III).
>>It is known that ionotropic glutamate receptor systems are involved in the central stimulation of gastric acid secretion,
because central (into the lateral cerebroventricule, nucleus raphe pallidus, nucleus raphe obscurus) injection of kainate and NMDA stimulated GAS [4, 9, 10]. But kainate bilaterally microinjected into the arcuate nucleus induced an inhibition of pentagastrin stimulated GAS [6]. Also, it was reported that L-Glutamate injected intravenously had no effect on basal GAS [7, 8].
Ionotropic glutamate receptors are also present in the peripheral neurons of gastrointestinal tract [5]. In our work we test the hypothesis that glutamate, the major excitatory neurotransmitter of the CNS, is also an excitatory neurotransmitter in the enteric nervous system. Therefore, we investigated the influence of antagonist of AMPA/kainate receptors IEM 1751 on basal GAS in rats with intact nervous system and after the bilateral vagotomy.
There is evidence of Glutamate/GABA acting on pain-sensing system (vallinoid receptors).
Capsaicin- and anandamide-induced gastric acid secretion via vanilloid receptor type 1 (TRPV1) in rat brain. Sachie Minowa, Satomi Ishihara, Shizuko Tsuchiya, Syunji Horie and Toshihiko Murayama. Chemical Pharmacology, School of Pharmaceutical Sciences, Chiba University, Japan. Brain Research 1039 (1-2):75-83 (2005).
The activation of transient receptor potential vanilloid receptor 1 (TRPV1) by capsaicin in rat brain stimulates gastric acid secretion via tachykinin NK2 receptors and the vagus cholinergic nerve, but the involvement of other receptor systems has not been elucidated. We investigated the role of the glutamate and γ-amino-butyric acid (GABA) receptor systems on the capsaicin response. Gastric acid secretion stimulated by the injection of capsaicin (30 nmol) into the lateral cerebroventricle (i.c.v.) was inhibited by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, an antagonist of non-N-methyl-d-aspartate (non-NMDA) receptors, 10.9 nmol, i.c.v.) and bicuculline (a GABAA receptor antagonist, 222 μg kg−1 10 min−1, i.v. infusion). Secretion stimulated by the injection of capsaicin (50 nmol) into the fourth cerebroventricle was inhibited by CNQX and bicuculline. I.c.v. injection of anandamide (an endogenous ligand of TRPV1 and cannabinoid receptors, 30 and 100 nmol) stimulated gastric acid secretion, and the response was inhibited by an antagonist of TRPV1 and in the capsaicin-treated rats, but not by an antagonist of cannabinoid receptors. In conclusion, the TRPV1 system, which is activated by capsaicin and anandamide, is preferentially coupled with non-NMDA and GABAA receptor systems in the brain and stimulates gastric acid secretion in rats.
Chrl42 astutely notes:
"I don't know if it's due to caffeine, but I listen to my pee-reactive time Cool and body reaction.
When drinking Black, I often witness my body cooled off quickly, and pee quick.
When drinking Wuyi, I feel my body warmed up and pee late.
Cooling off = glutamate clamping of NO in peripheral circulatory tract, that is vasoconstriction that results in reduced blood flow and 'cooling' effect, in the absence of theanine which counters glutamate effect on vascular system.
Peeing = brain (epinephrine) release temporarily increases urine production.
Mar 11th, '09, 15:15
Posts: 544
Joined: Feb 27th, '08, 10:06
Scrolling: scrolling
Location: TX <- NY
Contact:
silverneedles
i like detailed information (tho not a fan of singular studies or those based on rats, cell cultures) ...but i sometimes fail to see how it applies:
- i dont follow what youre saying/quoting about the gastric acid...
(i know acid secretion is stimulated by aminoacid(theanine being an aa) presence in the stomach, also acid is stimulated by the methylxanthines in tea (caffeine etc)
- are you saying there is enough glutamate in ingested tea that it vasoconstrics the entire vascular system of people, is this a general effect or an exception?
- i thought ingesting tea (because of the methylxanthines incl caffeine,theophylline) produces some diuresis (pee) by the direct renal action of methylxanthines coupled with the ingestion of all the water in tea.
I thought leaf is green because of chlorophyll, low chlorophyll = white leaf?
- i dont follow what youre saying/quoting about the gastric acid...
(i know acid secretion is stimulated by aminoacid(theanine being an aa) presence in the stomach, also acid is stimulated by the methylxanthines in tea (caffeine etc)
- are you saying there is enough glutamate in ingested tea that it vasoconstrics the entire vascular system of people, is this a general effect or an exception?
- i thought ingesting tea (because of the methylxanthines incl caffeine,theophylline) produces some diuresis (pee) by the direct renal action of methylxanthines coupled with the ingestion of all the water in tea.
I thought leaf is green because of chlorophyll, low chlorophyll = white leaf?
In lieu of direct experimentation on humans, animal models are employed; isolated cells and cell culture, as well as microbial reporter systems, are being used to clarify and in some cases, replace, use of live animals.
If you have ever experimented on rat models, you never forget the smell of harvesting tissue. Believe me, it's a strong inducer to work on 'clean' tissue culture or microbial expression systems.
WARNING! MIND NUMBING DETAIL FOLLOWS!
>i dont follow what youre saying/quoting about the gastric acid...
Production of theanine in plants is coupled to nitrogen cycling. Theanine is a structural analog of glutamate. Glutamate is an excitatory neurochemical, acting through cholinergic and possibly other, atypical receptors that affect gastric activity. Interestingly, it appears to act on the vagal reflex.
We have a couple of reports here and elsewhere on nausea and vomiting associated with green, but not other, tea ingestion. Also with skin reaction.
Some nerve cells in skin have been shown to be glutamate sensitive.
>- are you saying there is enough glutamate in ingested tea that it vasoconstrics the entire vascular system of people, is this a general effect or an exception?
Not a general effect in all people. Occurs in patients who have poor free radical scavenging and inefficient vascular elasticity, and its peripheral tissue, hands, feet/legs, and even nose and ears, that is affected.
>- i thought ingesting tea (because of the methylxanthines incl caffeine,theophylline) produces some diuresis (pee) by the direct renal action of methylxanthines coupled with the ingestion of all the water in tea.
Yes. In normal individuals, renal tubule response is small. In others that also have aldosterone sensitivity, the effect can be made worse because ADH-induced thirst reflex is impaired. If your liquid intake is small, you have sodium/potassium imbalance, and are chronically dehydrated - you *may* have abnormal ACTH release and/or epinephrine response at receptors as well.
>I thought leaf is green because of chlorophyll, low chlorophyll = white leaf?
More to do with the processing, apparently.
From Wikipedia:
"White tea contains higher catechin levels than green tea due to its lack of processing.[5] Catechin concentration is greatest in fresh, unbroken and unfermented tea leaves.[6] Furthermore, one study examining the composition of brewed green and white teas found that white tea contained more gallic acid and theobromine.[7]
(Catechins are polyphenolic antioxidant plant metabolites).
As white tea is made out of young leaves and buds, it is said to have more of the amino acid theanine (has relaxing and mood-enhancing properties) than green and black teas which are made from older leaves.
Caffeine content of green and white teas are similar [or maybe lower than some green teas] though both depend on factors such as the variety of tea, the cut and length of the leaf, and the method of steeping."
If we suspect that theanine, caffeinates and glutamate/alanine concentrations may induce excess gastric activity in SOME individuals, then the first step maybe to stay away from Japanese greens, to look to Chinese greens and white teas that MAY not induce excessive gastric response.
I also suggest that the thread petitioner look to GERD as a probable culprit for their gastric sensitivity to Japanese green teas.
http://www.gicare.com/Diets/GERD.aspx
If abnormal relaxation of the lower esophageal muscles is the culprit in acid reflux disease, then theanine inhibitory action on excitatory NMDA (structurally related to both excitatory glutamate and inhibitory GABA, and theanine) receptors responsible for GI tonus.
GABA, theanine and glutamate all have "u-shaped" activity curves for their receptors. Too much and too little are implicated in abnormal cellular responses in numerous cell systems.
Thats an entirely different situation from excessive gastric acid release/pH.
In this case, normally desirable quantities of theanine in some green teas might cause GERD, a condition often assumed to be coupled with excess stomach acid.
Thus, you have individuals reporting on the Internet that green tea and also theanine supplements caused them to vomit in their sleep - a dangerous situation. This is contrary to normal expectation and caused health-care specialists to scratch their heads, as theanine is *rarely* reported to cause adverse side effects.
To add to the confusion:
Insufficient gastric acid production (from low glutamate and/or excess theanine competing for glutamanergic receptors), is yet another cause of GI distress, and is common in older individuals (as is GERD).
If you have ever experimented on rat models, you never forget the smell of harvesting tissue. Believe me, it's a strong inducer to work on 'clean' tissue culture or microbial expression systems.
WARNING! MIND NUMBING DETAIL FOLLOWS!
>i dont follow what youre saying/quoting about the gastric acid...
Production of theanine in plants is coupled to nitrogen cycling. Theanine is a structural analog of glutamate. Glutamate is an excitatory neurochemical, acting through cholinergic and possibly other, atypical receptors that affect gastric activity. Interestingly, it appears to act on the vagal reflex.
We have a couple of reports here and elsewhere on nausea and vomiting associated with green, but not other, tea ingestion. Also with skin reaction.
Some nerve cells in skin have been shown to be glutamate sensitive.
>- are you saying there is enough glutamate in ingested tea that it vasoconstrics the entire vascular system of people, is this a general effect or an exception?
Not a general effect in all people. Occurs in patients who have poor free radical scavenging and inefficient vascular elasticity, and its peripheral tissue, hands, feet/legs, and even nose and ears, that is affected.
>- i thought ingesting tea (because of the methylxanthines incl caffeine,theophylline) produces some diuresis (pee) by the direct renal action of methylxanthines coupled with the ingestion of all the water in tea.
Yes. In normal individuals, renal tubule response is small. In others that also have aldosterone sensitivity, the effect can be made worse because ADH-induced thirst reflex is impaired. If your liquid intake is small, you have sodium/potassium imbalance, and are chronically dehydrated - you *may* have abnormal ACTH release and/or epinephrine response at receptors as well.
>I thought leaf is green because of chlorophyll, low chlorophyll = white leaf?
More to do with the processing, apparently.
From Wikipedia:
"White tea contains higher catechin levels than green tea due to its lack of processing.[5] Catechin concentration is greatest in fresh, unbroken and unfermented tea leaves.[6] Furthermore, one study examining the composition of brewed green and white teas found that white tea contained more gallic acid and theobromine.[7]
(Catechins are polyphenolic antioxidant plant metabolites).
As white tea is made out of young leaves and buds, it is said to have more of the amino acid theanine (has relaxing and mood-enhancing properties) than green and black teas which are made from older leaves.
Caffeine content of green and white teas are similar [or maybe lower than some green teas] though both depend on factors such as the variety of tea, the cut and length of the leaf, and the method of steeping."
If we suspect that theanine, caffeinates and glutamate/alanine concentrations may induce excess gastric activity in SOME individuals, then the first step maybe to stay away from Japanese greens, to look to Chinese greens and white teas that MAY not induce excessive gastric response.
I also suggest that the thread petitioner look to GERD as a probable culprit for their gastric sensitivity to Japanese green teas.
http://www.gicare.com/Diets/GERD.aspx
If abnormal relaxation of the lower esophageal muscles is the culprit in acid reflux disease, then theanine inhibitory action on excitatory NMDA (structurally related to both excitatory glutamate and inhibitory GABA, and theanine) receptors responsible for GI tonus.
GABA, theanine and glutamate all have "u-shaped" activity curves for their receptors. Too much and too little are implicated in abnormal cellular responses in numerous cell systems.
Thats an entirely different situation from excessive gastric acid release/pH.
In this case, normally desirable quantities of theanine in some green teas might cause GERD, a condition often assumed to be coupled with excess stomach acid.
Thus, you have individuals reporting on the Internet that green tea and also theanine supplements caused them to vomit in their sleep - a dangerous situation. This is contrary to normal expectation and caused health-care specialists to scratch their heads, as theanine is *rarely* reported to cause adverse side effects.
To add to the confusion:
Insufficient gastric acid production (from low glutamate and/or excess theanine competing for glutamanergic receptors), is yet another cause of GI distress, and is common in older individuals (as is GERD).
Mar 12th, '09, 01:42
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silverneedles
sure, but it does not mean it can automatically be applied to humans.
thats why there are hundreds of ideas and experiments but in the end just a couple end up useful.
id rather take a mouse than a human equivalent.
>>"Theanine is a structural analog of glutamate"
right
but does that mean that theanine will act like glutamate-on the same receptors ?(in humans)
--------
again, i have trouble following the words, and understanding the mechanisms you are detailing. i am sorry but they seem like randomly picked statements and i cant interconnect them... or maybe i should hit books again. hit myself with the books for not understanding main concepts...
#1
i dont know what disease that is, or is a part of...
"inefficient vascular elasticity"
... doesnt that cover the entire elderly population?
i'm pretty sure Chrl42 is not that person with poor free radical scavenging activity AND inefficient vascular elasticity, intertwined with some glutamate-NO vasoconstrictive mechanism...
#2
i havent encountered a disease of increased aldosterone sensitivity- which i'd understand as regular aldosterone creating excessive effect.
>"ADH-induced thirst reflex"
what is the ADH induced thirst reflex? i havent heard ADH inducing the thirst reflex.
yes they are related. increased osm leads to increased ADH to retain water but then the extra water would not induce the thirst reflex...
>"have aldosterone sensitivity, the effect can be made worse because ADH-induced thirst reflex is impaired" ..."chronically dehydrated"
but extra aldosterone effect = retains Na AND Water, so why would there be dehydration?
so this situation of too much aldosterone effect and some ADH thing doesnt make ANY sense to me...
#3
what normal processing methods turn a green leaf white. and what normal processing methods turn a white leaf green?
so how does that wiki quote relate to the color of a leaf ???
you said its the processing. there is a huge quote there that has nothing to do with explaining what youre talking about.
#4
is there a common occurrence of EXCESS THEANINE IN THE ELDERLY???
the MAIN cause of low acid in the elderly is not low glutamate.
thats why there are hundreds of ideas and experiments but in the end just a couple end up useful.
id rather take a mouse than a human equivalent.
>>"Theanine is a structural analog of glutamate"
right
but does that mean that theanine will act like glutamate-on the same receptors ?(in humans)
--------
again, i have trouble following the words, and understanding the mechanisms you are detailing. i am sorry but they seem like randomly picked statements and i cant interconnect them... or maybe i should hit books again. hit myself with the books for not understanding main concepts...
#1
" patients who have poor free radical scavenging">- are you saying there is enough glutamate in ingested tea that it vasoconstrics the entire vascular system of people, is this a general effect or an exception?
Not a general effect in all people. Occurs in patients who have poor free radical scavenging and inefficient vascular elasticity, and its peripheral tissue, hands, feet/legs, and even nose and ears, that is affected.
i dont know what disease that is, or is a part of...
"inefficient vascular elasticity"
... doesnt that cover the entire elderly population?
i'm pretty sure Chrl42 is not that person with poor free radical scavenging activity AND inefficient vascular elasticity, intertwined with some glutamate-NO vasoconstrictive mechanism...
#2
>"others that also have aldosterone sensitivity">- i thought ingesting tea (because of the methylxanthines incl caffeine,theophylline) produces some diuresis (pee) by the direct renal action of methylxanthines coupled with the ingestion of all the water in tea.
Yes. In normal individuals, renal tubule response is small. In others that also have aldosterone sensitivity, the effect can be made worse because ADH-induced thirst reflex is impaired. If your liquid intake is small, you have sodium/potassium imbalance, and are chronically dehydrated - you *may* have abnormal ACTH release and/or epinephrine response at receptors as well.
i havent encountered a disease of increased aldosterone sensitivity- which i'd understand as regular aldosterone creating excessive effect.
>"ADH-induced thirst reflex"
what is the ADH induced thirst reflex? i havent heard ADH inducing the thirst reflex.
yes they are related. increased osm leads to increased ADH to retain water but then the extra water would not induce the thirst reflex...
>"have aldosterone sensitivity, the effect can be made worse because ADH-induced thirst reflex is impaired" ..."chronically dehydrated"
but extra aldosterone effect = retains Na AND Water, so why would there be dehydration?
so this situation of too much aldosterone effect and some ADH thing doesnt make ANY sense to me...
#3
how is that?"I thought leaf is green because of chlorophyll, low chlorophyll = white leaf?
More to do with the processing, apparently.
what normal processing methods turn a green leaf white. and what normal processing methods turn a white leaf green?
chlorophyll is not a catechin.>I thought leaf is green because of chlorophyll, low chlorophyll = white leaf?
More to do with the processing, apparently.
From Wikipedia:
"White tea contains higher catechin levels than green tea due to its lack of processing.[5] Catechin concentration is greatest in fresh, unbroken and unfermented tea leaves.[6] Furthermore, one study examining the composition of brewed green and white teas found that white tea contained more gallic acid and theobromine.[7]
(Catechins are polyphenolic antioxidant plant metabolites).
As white tea is made out of young leaves and buds, it is said to have more of the amino acid theanine (has relaxing and mood-enhancing properties) than green and black teas which are made from older leaves.
Caffeine content of green and white teas are similar [or maybe lower than some green teas] though both depend on factors such as the variety of tea, the cut and length of the leaf, and the method of steeping."
so how does that wiki quote relate to the color of a leaf ???
you said its the processing. there is a huge quote there that has nothing to do with explaining what youre talking about.
#4
there is no IF, you cant have _reflux_ thru a closed door.If abnormal relaxation of the lower esophageal muscles is the culprit in acid reflux disease
what does that mean? what does excess theanine have to do with elderly health problems??Insufficient gastric acid production (from low glutamate and/or excess theanine competing for glutamanergic receptors)...common in older individuals"
is there a common occurrence of EXCESS THEANINE IN THE ELDERLY???
the MAIN cause of low acid in the elderly is not low glutamate.