Thyroid-inhibiting amino acids
#1
One of the most interesting ideas I learned through Peat is that some amino acids inhibit thyroid activity. The study he mentions is available in full for free:
 
http://www.scielo.br/pdf/bjmbr/v33n3/3596m.pdf
 
The authors state that cysteine, tryptophan, and methionine completely inhibited TPO oxidation activity at a concentration of 50 micromoles. Tyrosine, phenylalanine, and histamine caused partial inhibition, while the other amino acids caused no inhibition.
 
I don't have a science background, so I wanted to figure out if this concentration is typical of what is found in human blood. I looked at a sample report for plasma amino acids, which you can see if you click on "Sample Report" on this Life Extension Foundation page:
 
http://www.lifeextension.com/Vitamins-Su...Blood-Test
 
In this sample report, the reference range for cystine is 13.5-60.2 micromoles/liter, methionine is 12.7-41.1 micromoles/liter, and tryptophan is 23.5-90.0 micromoles/liter. If the in vitro experiment results can be applied to human blood, then the concentration of 50 micromoles that completely inhibited TPO oxidation activity is definitely possible in the real world.
 
However, this is a bit difficult to believe. If TPO oxidation activity can be completely inhibited by these amino acids, a person would have absolutely NO levels of thyroid hormone. Since laboratory reference ranges are developed through patient results, there must be a significant number of people whose blood contains supposedly dangerous levels of the thyroid-inhibiting amino acids. Yet we don't see an epidemic of people dropping dead due to a complete lack of thyroid hormones.

As mentioned, I don't have a science background; I'm just trying to figure out how much this experiment applies to human bodies. Perhaps the inhibitory effects of these amino acids are mitigated by other factors.
 
Any thoughts? Thanks!
#2
TSH directly drives thyroid peroxidase activity. This in vitro study
did not take TSH into account. It is very likely that inhibition caused
by high concentration of  cysteine, tryptophan, and methionine
is compensated by higher level of TSH. It would be interesting to see
how serum TSH level correlates with these amino acids concentration.
#3
(06-25-2017, 06:09 PM)Mittir Wrote: TSH directly drives thyroid peroxidase activity. This in vitro study
did not take TSH into account. It is very likely that inhibition caused
by high concentration of  cysteine, tryptophan, and methionine
is compensated by higher level of TSH. It would be interesting to see
how serum TSH level correlates with these amino acids concentration.

Are you saying that TSH's stimulting effect on thyroid peroxidase activity would offset the amino acids' inhibiting effect? This is what I'm thinking also. There are probably other compounds besides TSH that would also stimulate thyroid peroxidase.

It's interesting that tyrosine, which is a fundamental component of T4, also had an inhibiting effect on thyroid peroxidase.

I'm just trying to figure out how "worried" we really need to be about cysteine, tryptophan, and methionine. It seems that some Peat followers become overly paranoid in regards to this.
#4
(06-25-2017, 06:09 PM)Mittir Wrote: TSH directly drives thyroid peroxidase activity. This in vitro study
did not take TSH into account. It is very likely that inhibition caused
by high concentration of  cysteine, tryptophan, and methionine
is compensated by higher level of TSH. It would be interesting to see
how serum TSH level correlates with these amino acids concentration.

Excellent mittir, glad you're here!
[color=#222222][size=medium]"I have no religion, no political affiliation: I believe in me, above everything else." -Chasing Good & Evil[/size][/color]
#5
Thyroid inhibition probably happens by poor amino acid intake or malnutrition just as much as it happens with the ''wrong'' amino-acids. However, I don't agree with Peat's views on histamine 100%, because histamine helps to balance the brain and level ones sanity. Almost every schizophrenic has low histamine H1R's [1] and low histamine levels [2] and many with Dementia have abnormally low histamine receptors [3]. So Peat is wrong about that part; histamine is not a ''bad'' substance per se. It just can't be too high or too low. With that being said, antihistamines aren't necessarily bad either. It depends on how much you are using, when and for what. It also depends on which generation of antihistamine you are using, in relation to health effects - and whether that antihistamine has estrogenic effects (as declared like Claritin does).

Also, histamine has benefits on Sight.

See here my article..
#6
(07-04-2017, 06:51 PM)Area-1255 Wrote: Thyroid inhibition probably happens by poor amino acid intake or malnutrition just as much as it happens with the ''wrong'' amino-acids. However, I don't agree with Peat's views on histamine 100%, because histamine helps to balance the brain and level ones sanity. Almost every schizophrenic has low histamine H1R's [1] and low histamine levels [2] and many with Dementia have abnormally low histamine receptors [3]. So Peat is wrong about that part; histamine is not a ''bad'' substance per se. It just can't be too high or too low. With that being said, antihistamines aren't necessarily bad either. It depends on how much you are using, when and for what. It also depends on which generation of antihistamine you are using, in relation to health effects - and whether that antihistamine has estrogenic effects (as declared like Claritin does).

Also, histamine has benefits on Sight.

See here my article..

Hi Area-1255,

I've come across your website several times in the past. It's quite interesting! Hope you keep it up.
#7
(07-04-2017, 06:51 PM)Area-1255 Wrote: So Peat is wrong about that part; histamine is not a ''bad'' substance per se.  It just can't be too high or too low
Isn't that true for everything, at least, in our body? I mean, even serotonin or whatever people like to blame. The dose is what makes the poison. But ok, perhaps there are certain chemicals that deserve more attention than others.
#8
(07-07-2017, 08:02 PM)9e10 Wrote:
(07-04-2017, 06:51 PM)Area-1255 Wrote: So Peat is wrong about that part; histamine is not a ''bad'' substance per se.  It just can't be too high or too low
Isn't that true for everything, at least, in our body? I mean, even serotonin or whatever people like to blame. The dose is what makes the poison. But ok, perhaps there are certain chemicals that deserve more attention than others.

Yes, that's one of my main issues with Peat. He takes a substance that can cause problems when excessive and then assumes that it's dangerous at any level. For heaven's sake, the man is afraid of eating pineapples because he's worried about the serotonin!
  


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