Is There L-Glutamine in Pea Protein?

Reputable sources only list glutamic acid, a nonessential amino acid, in pea protein, which the body readily synthesizes and that readily converts into l-glutamine inside our bodies. Glutamine and glutamic acid typically comprise between 5% and 15% of dietary proteins, but we require so much of these two amino acids that most of our fairly large body stores are actually synthesized endogenously (internally). 

Glutamine is used to make glucosamine and is required by the immune system, for wound healing, for acid-base balance, for brain function, and for gluconeogenesis. Both amino acids are conditionally essential during pregnancy, lactation, and growth phases. 

Commercially produced MSG is related to, but not identical to, glutamine because it is a salt of glutamine; a glutamate, rather than an amino acid found in common proteins. Glutamate has been classified as an excitotoxin that can overexcite our nervous systems; but that is dependent on the brain lacking proper controls, such as can be provided by the essential nutrients magnesium and antioxidants. 

This study indicates that pea protein contains glutamic acid, not l-glutamine:  

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6245118/

Protein content and amino acid composition of commercially available plant-based protein isolates (nih.gov)

What is Taurine and how is it made?

Taurine is a nature-identical/natural form amino acid that’s commercially synthesized from common chemicals. It’s made from the reaction of sulfuric acid with mono-ethanol amine; also known as ethanolamine; which is an amino alcohol that’s also part of phospholipids, like the phosphatidylethanolamine (PE) in lecithin, that are important components of cell membranes. 

Taurine, a sulphur-containing amino acid, is the most abundant intracellular amino acid in humans, and is involved in numerous biological and physiological functions, including bile production and heart health. Once we pass infancy, we routinely synthesize taurine in our bodies from the amino acids methionine and cysteine with the aid of vitamin B₆. That makes it a nonessential amino acid for most of us; though specific groups of individuals are at risk for taurine deficiency and may benefit from supplementation. 

I personally take 1,000 mg of taurine twice a day for heart heath now, as I have had troubling arrhythmia incidents send me to the emergency room and am medically at risk for progressively worse outcomes over time. It has shown effectiveness in increasing exercise capability in heart failure patients and arterial compliance to nitric oxide to support healthy blood pressure. I also take l-carnitine, olive leaf extract, magnesium, l-citrulline, Pycnogenol, grape seed extract, hawthorn leaf and flower extract, a good multivitamin, and other supplements to support my cardiovascular health and hold off that disturbing prognosis as long as possible. 

Taurine has no d- or l- forms, similar to glycine but unlike most amino acids that have different optical rotations in distinct natural and synthetic forms. All taurine is the natural form, even if produced by chemical synthesis, whether commercially or in our bodies. 

Thyroid supplements

People typically seek thyroid support nutrients as a way to enhance their energy levels, enable proper control of their body temperature, and support a strong metabolic rate.  We take these nutrients, both individually and in formulas, in order to assure adequate levels to support optimal thyroid function, since a deficiency or insufficiency of key nutrients could reduce the operational efficiency of the thyroid gland.   Proper thyroid function supports a lean body composition and helps prevent fatigue.  Under the control of complex feedback and signals from the hypothalamic-pituitary-thyroid axis, the thyroid gland regulates body temperature and metabolism rates, playing an important role in weight management and energy states.  By the same token, if any of the important nutrients are not available to the thyroid in sufficient amounts, metabolic rates and energy levels could suffer. ¹

Natural thyroid support supplements work primarily by providing precursors of thyroid hormones, along with various cofactors, in order to encourage proper thyroid function.  In some cases, the lack of adequate nutritional resources prevent the thyroid gland from maintaining optimal efficiencies, and if the gland can’t maintain healthy levels of its important hormones, then it can’t adequately support the body’s metabolism.  Unlike medical treatments, nutritional approaches focus on providing what the body needs in order to assure that the thyroid has its particular needs met and can function optimally. 

The key nutrients for thyroid function are the mineral Iodine and the natural amino acid L-Tyrosine. 

Humans require iodine for cellular metabolism and for normal thyroid function; specifically for the production of thyroid hormones.  Thyroid hormones regulate many important biochemical reactions, including protein synthesis and enzymatic activity, and are critical determinants of metabolic activity.  Iodine is a nutrient that can sometimes be obtained from the soil, but many soils are deficient.  Areas that are mountainous, very rainy, or prone to floods/erosion tend to have soils that are low in iodine, increasing the risk that foods grown in those areas will be iodine-deficient.  Table salt is commonly iodized, but those using non-iodized salt or on low-sodium diets can’t rely on that source.  Multivitamin formulas, thyroid support formulas, kelp and some other seaweeds, and some multimineral formulas provide supplemental iodine.  The U.S. Recommended Dietary Allowance (RDA) is 150 mcg (micrograms) daily for adults ages 18 and older, 220 mcg daily for pregnant women, and 290 mcg daily for lactating women. The Tolerable Upper Intake Levels (UL) for adults ages 18 and older is 1,100 micrograms daily. ^{2-3 ]}

The common sources of iodine in dietary supplements include Potassium Iodide, Kelp, and other seaweeds.  While kelp and some seaweeds are fine for getting the relatively low RDA level of iodine intake, those seeking much higher levels are usually advised to consider Potassium Iodide.  This is because seaweeds typically contain less than 1% iodine, along with a lot of other metals and minerals - including some that we may want to avoid getting too much of - so consuming high doses of seaweeds on a daily basis may not be our safest option.  And iodine is a mineral nutrient that needs to be replenished daily.

L-Tyrosine is an amino acid that is important to the structure of most proteins in the body. It is also the precursor of a number of neurotransmitters and hormones, including the major catecholamines dopamine, norepinephrine, and epinephrine (adrenaline), which are stress hormones made by the adrenal glands.  In addition to these functions, tyrosine also helps produce melanin (the pigment responsible for hair and skin color) and helps in the function of the adrenal, thyroid, and pituitary glands.  Because of these varied responsibilities and the ability of various stresses and dietary deficiencies to reduce tyrosine levels, people sometimes supplement tyrosine (as natural L-Tyrosine) in order to support proper thyroid function. ^4-5   

How do Iodine and L-Tyrosine affect thyroid function?  The thyroid gland’s epithelial cells prepare large quantities of tyrosine into a glycoprotein “scaffold” that is the structural backbone used to form the thyroid hormones thyroxine (T4) and triiodothyronine (T3).  The scaffold and iodine are both secreted into the lumen of the thyroid gland, where an enzyme facilitates the hormone synthesis.  Other enzymes then separate the hormones from the scaffolding in steps, liberating them into their circulating forms.  A few tyrosines are incorporated into these hormones, but most are left in the scaffolding structure’s remains that will be recycled by the body. 

Selenium is an essential mineral nutrient that is necessary for normal thyroid hormone metabolism.  Selenium-containing enzymes control the synthesis and degradation of the biologically active thyroid hormone, T3.  Selenium deficiency may worsen the effects of iodine deficiency on thyroid function, and adequate selenium nutritional status may help protect against some of the neurological effects of iodine deficiency.   Additionally, selenium-based antioxidant enzymes protect the thyroid gland from peroxides produced during the synthesis of these hormones. ^{2, 3, 6}

Zinc, another essential mineral responsible for hundreds of critical chemical reactions in the healthy human, is also important for maintaining normal thyroid homeostasis. Its complex roles include effects on both the synthesis and mode of action of the hormones.  Thyroid hormone binding transcription factors, which are essential for modulating gene expression, contain zinc bound to cysteine-related compounds.   In some studies, low zinc status was associated with decreased thyroid hormone levels.  ³

Copper is believed to have a role in thyroid hormone function, perhaps related to selenium status. ³

Guggul (Commiphora mukul) is an Indian Ayurvedic herb that contains the active compound Guggulsterone, which has been shown to stimulate thyroid activity. ^7-8

 
These ingredients, both singly and as thyroid support formulas, are in demand by consumers wanting to assure adequate thyroid function in times of dietary insufficiencies and various stresses.  Of course, these nutrients and their many functions in the body have a host of potential benefits to those supplementing with them if they may not get adequate amounts from their diet for their individual requirements. 

 

REFERENCES

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1.  Zoeller RT, Tan SW, Tyl RW. General background on the hypothalamic-pituitary-thyroid (HPT) axis. Crit Rev Toxicol. 2007 Jan-Feb;37(1-2):11-53. Review. PubMed PMID: 17364704.
2. http://ods.od.nih.gov/factsheets/Iodine-HealthProfessional/
3. Arthur JR, Beckett GJ. Thyroid function. Br Med Bull. 1999;55(3):658-68. Review. PubMed PMID: 10746354.
4. http://www.umm.edu/altmed/articles/tyrosine-000329.htm
5. http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/thyroid/synthesis.html
6. http://ods.od.nih.gov/factsheets/selenium/
7. http://www.drugs.com/npp/guggul.html
8. http://www.peoplespharmacy.com/2005/10/18/guggul/

How proteins are digested to liberate amino acids

Digestion is obtained by actions of stomach acid (low pH) and enzymes both in the stomach & intestines (pancreatic protease). In the acidic environment of the stomach, the negatively charged side chains are removed by pepsin. In the more alkaline environment of the intestine, the positively charged side chains are removed by trypsin. In the stomach, Pepsin helps to "unwind" the proteins and breaks the bonds between the amino acids in certain places. In the small intestine other enzymes break the bonds between different amino acids than pepsin does. Because proteins are such complicated molecules it takes a long time and more than one enzyme to completely break them down into amino acids. Digestion results in about 60% small peptides (or peptide bound), which are longer chains of amino acids, and 40% free amino acids (free form). Peptides can be further broken down by hydrolysis in enterocytes (intestinal absorptive cells, simple columnar epithelial cells found in the small intestines and colon).

All proteins are naturally hydrolyzed by stomach acid during normal digestion and the amounts in mineral chelates are in milligram, not gram, strengths. Fermentation to make healthy foods like cheese, vinegar, yogurt, miso, etc. also digests proteins and liberates amino acids, which are of course essential to human nutrition.

Although the excitatory amino acids aspartic acid and glutamic acid are not essential amino acids, the body can create them from numerous sources. In fact, glutamine is the major circulating amino acid and the brain will break down muscles to get it for fuel if the blood sugar is too low to support brain function. Glutamine also fuels some intestinal cells.

What is the difference between L-Taurine and Taurine, or between L-Glycine and Glycine?

What is the difference between L-Taurine and Taurine, or between L-Glycine and Glycine? The natural forms of amino acids are typically the “L form”, as in L-arginine, L-cysteine, etc. Synthetic forms are denoted as “D forms”, such as D-Methionine and D-Carnitine. But there are 2 aminos that have only one form without these variations: Glycine and Taurine. These two aminos are sometimes called L-Taurine or L-Glycine, but are more properly called just “Taurine” and “Glycine”. Regardless of the name used, they are always natural amino acids. Technical explanation: Most aminos have a property that, when the molecule is put into a solution, it will polarize and rotate light either to the left or right. The Greek words denoting left and right are Levo for left and Dextro for right, so the letters L and D are used to distinguish these forms. This polarization and rotation of light is called “optical rotation”. The differing L and D forms are called stereoisomers. For amino acids that polarize light, the L form is the natural form. However, Taurine is an amino acid that does not polarize light. It thus is properly called just “Taurine”, without L or D configurations. While some label Taurine as “L-Taurine”, that name is not technically correct. “Taurine” is the same exact molecule and form as what is commonly mislabeled as “L-Taurine”. There is another amino acid that lacks a potential optical rotation. Glycine is a very simple molecule that comes only as “Glycine”, also lacking different L or D stereoisomer forms. The D forms of amino acids sold commercially are considered to be synthetic. However, D forms of amino acids are not always synthetic. There are several D forms that exist in nature. In addition, amino acids can be racemized by the body and go back and forth between the D form and the L form quite easily. However, only L forms can be incorporated into proteins. For the purposes of dietary supplements, the L forms are natural and the D forms are synthetic. DLPA and DL-methionine are actually racemic mixtures of both L and D forms. But there is no such thing as D-Taurine or D-Glycine; in other words, no synthetic forms exist of these two aminos since each only comes as one isomer that doesn’t polarize and rotate light to the right. Nor are there really L forms of these, since they do not polarize and rotate light to the left, either. There are simply single, natural isomers of just plain Glycine and Taurine. Don’t assume that all D or L forms of molecules are good or bad, since it really depends on the individual substance concerned. For example, the D isomers of vitamin E are the natural forms and the L isomers are synthetic; just the opposite of amino acids. Thus the terminology and forms of what is natural or synthetic will vary by substance. Some natural molecules exist as L form, some as D form and some have only one form, whether in food or if synthesized. Look for companies that only sell natural form amino acids and Vitamin E and use the correct scientific names for substances and compounds on their labels. Provided by Neil E. Levin, CCN, DANLA Board certified clinical nutritionist with diplomate in advanced nutritional laboratory assessment 6/8/2007