Sélénium choix

Selon la source des infos (de sources scientifiques), il y a plusieurs types de sélénium qui peuvent convenir, selon les circonstances.
En gros, nous avons:
la séléniométhionine  et la  séléniocystéine. On oublie les sels inorganiques, un moment.
Mais quid du du sélénium complexé avec un acide aminé?
Je prends actuellement ce dernier type, du sélénium glycinate complex, avec un multi-enzyme, de chez Vitacost.
Contient aussi des FOS (prébiotique), du gingembre, du poivre noir.
Exicpients; farine de riz, stearate de Mg, gélatine végétale.
Chez vitacost.com. Prix super avantageux (offre 2 pour 1).
Il faudrait alterner les sources de méthionine et de cystéine.
100 mcg est bien. Ne pas dépasser 200 mcg, sauf en cas d'intox (temporairement 400 mcg).
Je recharge en sélénium avant de prendre de l'iode.
ça ne me réussit pas trop mal, avec 5 à 10' d’exposition de la thyroïde aux rayons infra-rouges, un jour sur deux. Ma T° corporelle semble enfin plus logique au lever. 36.2° Je viens souvent de 34.5°
Il fallait attendre 11H du mat pour que ça daigne monter à 35.5 ou 36°, avec  une protéine au petit déj. et un café vers 11H. Je carbure mieux maintenant.  
+ un complexe liposoluble (A, D3, E et K2 mk4) et un complexe de vitamine B bien dosé (sauf B9 et B12), fractionné en 2 prises (gouttes).

J'ai cet article en stock. On éliminera les sources qui proposent un supplément de Se. Pas neutre.
Les infos sont parfois divergentes.
Forms of selenium exits under 3 major forms:
- yeast
- sodium (selenite or selenate)
- amino acid (selenio-methionine or cysteine).
We usually find selenate or selenio-methionine (SM) on market.
Specialists classify Se in two main categories: Organic and inorganic. Salts are inorganic and are supposed to be less well absorbed by tissues. If we only refer to SM and Selenate, it’s not really true, as showed by studies.

Organic selenium
1. Selenomethionine (as L-selenomethionine) is formed in plants when selenium substitutes for sulfur during synthesis of the amino acid methionine, and becomes incorporated into proteins in place of methionine. It is the predominant form of selenium in Brazil nuts, cereals, legumes, and fish.
2. Selenocysteine, a selenium-containing amino acid. In humans, it is one of the 22 proteinogenic amino acids and is incorporated into 25 known selenoproteins during protein synthesis. These selenoproteins are vital to human health, and include the antioxidants glutathione peroxidase and selenoprotein P, the thioredoxin reductases, and the deiodinases involved in thyroid hormone activation.
3. Methylselenocysteine (also known as Se-methyl-selenocysteine) and its derivative gamma-glutamyl Se-methylselenocysteine are metabolic products of selenocysteine that are the predominant form of selenium in plants of the allium (onions, garlic) and brassica (cruciferous vegetables, e.g., broccoli, cabbage) families.

Inorganic Selenium
1. Selenite, used in supplements and the most common form of selenium used in pet foods.
2. Selenate is the predominant form of selenium in shellfish and vegetables (other than the allium and brassica families) grown in seleniferous soil.

Selenium-Enriched Yeast
The supplement known as selenium-enriched yeast is yeast grown in a medium containing inorganic selenium, usually sodium selenite. The selenium becomes organically bound to the yeast, mostly being incorporated into the yeast proteins. The supplement therefore consists predominantly of selenomethionine (between 60 and 80%), but also has small amounts of selenocysteine, methylselenocysteine and gamma-glutamyl Se-methylselenocysteine. Reputable manufacturers ensure that the majority (at least 90%) of the selenite is organically bound to the yeast; otherwise, the product may simply contain a mixture of inorganic selenite and yeast.
Note: Yeast is dead and there is no problem for people suffering from candidose.

What Form is Best?
Selenium in any form, whether from food or supplements, organic or inorganic, is utilized by the body for selenoprotein synthesis after first being metabolized to hydrogen selenide, the cellular storage form of selenium. Surplus selenium is converted to methylated metabolites and excreted via the urine and in the breath. Excessive buildup of hydrogen selenide can lead to its oxidation, resulting in the production of reactive oxygen species (ROS) leading to oxidative toxic effects in the body. Inorganic selenite also has pro-oxidant properties that can result in toxic effects when present in excess.
All forms of selenium are well absorbed, but absorption of selenomethionine is the best. It uses the same active transport mechanism as for methionine, one of the 9 essential amino acids that can only be obtained from the diet, and this increases the efficiency of absorption of selenomethionine over inorganic forms of selenium. Some supplements include vitamin E and it has been claimed that this facilitates selenium absorption, but there is no evidence that this is the case; vitamin E is included in some supplements because its antioxidant effects are synergistic with selenium.

Selenium Species with Anti-Cancer Effects
The anticancer effects of selenium differ depending on which form is used
See link for more details

How Much Selenium Do We Need?
When selenium levels are optimized there has been an observed decrease in the risks of prostate, lung, colorectal, and bladder cancer; however, excessive selenium supplementation in selenium-replete populations has been found to increase risk of type 2 diabetes. Additional selenium supplements, whether organic or inorganic, may therefore be detrimental to people with already adequate or high dietary selenium intake. The current recommended dietary allowance (RDA) in adults is 55 micrograms/day. Urine testing while maintaining the patient’s usual diet and supplementation can help determine whether selenium status is adequate, too low or too high.
For detailed recommended intakes and a list of selenium-containing foods, see the NIH Office of Dietary Supplements Dietary Supplement Fact Sheet: Selenium (for Health Professionals).

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References
Rayman MP, Infante HG, Sargent M. Food-chain selenium and human health: spotlight on speciation. Br J Nutr. 2008;100(2):238-53.
Rayman MP. Food-chain selenium and human health: emphasis on intake. Br J Nutr. 2008;100(2):254-68.
Rayman MP. Selenium and human health. Lancet. 2012;379(9822):1256-68.