Ingredient Repository · Ingredient

🌿
Ingredient

Selenium

Trace mineral essential for antioxidant glutathione peroxidase enzymes, thyroid hormone activation, and immune defense.

What it is

Selenium (as L-selenomethionine or sodium selenite) is an essential trace mineral incorporated into selenoproteins like glutathione peroxidase (GPx) and thioredoxin reductase. In Velobiotics products like Almasi Skin Hair Nails, Her-Biotics Ageless, His-Biotics Sport, and PregBiotics, selenium is delivered alongside microencapsulated probiotics to support immune defense and thyroid enzyme activity.

Also known as: Selenomethionine, Sodium Selenite

What it does

  • Forms the catalytic center of glutathione peroxidase, protecting cellular membranes from lipid peroxidation.
  • Cofactor for iodothyronine deiodinases, converting inactive thyroxine (T4) into active T3.
  • Enhances T-lymphocyte proliferation, NK-cell activity, and humoral immune responses.
  • Maintains skin, hair, and follicular tissue resistance against environmental oxidative stress.

Amplified by probiotics

L-selenomethionine is absorbed efficiently via intestinal amino acid transport pathways. Probiotic bacteria (Lactobacillus and Bifidobacterium) assimilate dietary inorganic selenium and convert it into highly bioavailable organic selenoproteins and selenium nanoparticles. Furthermore, probiotics reduce gut mucosal inflammation, protecting amino acid transporters on enterocyte brush borders. The combined activity of probiotic-derived antioxidants and host selenoproteins provides synergistic defense against gastrointestinal and systemic oxidative stress.

Typical dose

55–200 µg/day

The evidence

Evidence: strong

Randomized controlled human trials show selenium supplementation enhances glutathione peroxidase activity, improves thyroid autoimmune antibody profiles, and supports immune cell responsiveness. (Rayman MP. 2012, Lancet; Winther KH, et al. 2020, Nat Rev Endocrinol; Avery JC, Hoffmann PR. 2018, Nutrients).

  1. Rayman MP. Selenium and human health. Lancet. 2012;379(9822):1256-1268 PubMed ↗
  2. Winther KH, et al. Selenium in thyroid disorders - essential knowledge for clinicians. Nat Rev Endocrinol. 2020;16(3):165-176 PubMed ↗
  3. Avery JC, Hoffmann PR. Selenium, Selenoproteins, and Immunity. Nutrients. 2018;10(9):1203 PubMed ↗

Safety & who should check first

Tolerable Upper Intake Level is 400 µg/day for adults. Safe within standard nutritional ranges. High chronic doses (>800 µg/day) can lead to selenosis.