Selenium

Single-ingredient selenium reference formula at 200 mcg per serving, developed as a capsule or tablet.

Selenium is a reference formula for brands building a single-ingredient trace mineral product at a default amount of 200 mcg (0.2 mg) of elemental selenium per serving. Selenium is the only active ingredient, so the development work sits with a microgram-level mineral: the choice between an organic selenium form and an inorganic salt, the premix that carries it, and the content uniformity of each unit.

Capsule is the lead format because a selenomethionine premix blends into a standard fill, while the tablet uses the same premix in a compression system. Amounts of 50 and 100 mcg sit beside the default for brands that want a smaller tier, and the amount is a decision for the brand and its market review.

Ingredient Composition

IngredientPer ServingRaw Material FormAlternative Form (same amount of active)
Selenium200 mcg (default amount)L-selenomethionine as a premix on a carrier, specified on elemental selenium content; 200 mcg selenium per servingSodium selenite or selenium-enriched yeast, with the input recalculated to 200 mcg of elemental selenium

Amounts are stated as mcg of elemental selenium (Se, 78.97 g/mol; PubChem CID 6326970); 200 mcg equals 0.2 mg. Selenium content by weight follows from the molecular weight of each pure compound: selenomethionine is 40.3% selenium (CID 15103, 196.12 g/mol) and sodium selenite is 45.7% selenium (CID 24934, 172.95 g/mol). Yeast products carry selenium at a content set by the supplier assay.

Intended Benefits & Formula Rationale

This formula is designed for products positioned around daily selenium intake and trace mineral nutrition. Selenium is included as the only active so that the form, the amount and the premix can be set without interaction with other actives.

Intended Benefit DirectionKey IngredientsFormulation Rationale
Daily selenium intakeSeleniumIncluded because selenium is incorporated into selenoproteins with antioxidant and anti-inflammatory effects and a role in the production of active thyroid hormone [1]. Evidence: Referenced
Thyroid and immune nutritionSeleniumA review links low selenium status to poor immune function and reports a lower risk of autoimmune thyroid disease with higher status or supplementation, while stating that trials in cancer have been mixed and that benefit is expected only where intake is inadequate [1]. Evidence: Mixed

The amount is one stated tier, and the review in [1] describes a U-shaped link between selenium status and health, in which people with adequate-to-high status might be affected adversely by supplements. Amount, claims and target market are therefore brand decisions reviewed for each sales market.

Available Formats

The selenium reference formula is built for a capsule version and a tablet version; counts per serving are design choices that the brand can adjust.

FormatUnitPer ServingPack SizeOther Ingredients (typical)Suitability
Capsule1 capsule200 mcg60 or 100 capsulesCellulose, hypromellose shell, magnesium stearateLead format; premix in a small fill
Tablet1 tablet200 mcg60 or 120 tabletsCellulose, binder, disintegrant, lubricantCompressed unit

Raw Material Input & Fill (Design Estimate)

Design estimates. The input is the selenium amount divided by the selenium content of the compound at an assumed 100% assay, and the compound is carried in a 1% premix on a carrier. Selenomethionine at 40.3% selenium gives 0.50 mg of compound, or 50 mg of premix, for 200 mcg of selenium.

FormatRaw Material Input per UnitDesign FillBalance for ExcipientsVerification Before Scale-Up
Capsule50 mg premix (200 mcg selenium)150 mg per capsule100 mgBlend uniformity, fill weight variation, content assay of selenium
Tablet50 mg premix (200 mcg selenium)120 mg tablet weight70 mgContent uniformity, hardness, disintegration, content assay of selenium

Liquid and gummy versions are separate projects, because a microgram-level mineral in a dissolving or chewable system needs its own homogeneity and stability work.

Formulation Considerations

Micro-dose in a premix. At 0.5 mg of selenomethionine per unit the active is a tiny part of the blend. The premix dilution and a stepwise blending order are set first, and content uniformity of the first units decides whether the dilution holds.
Organic form or inorganic salt. Selenomethionine and sodium selenite carry different selenium percentages and different cost, handling and label wording. The form is stated on the formula and the label, and the supplier assay fixes the input weight.
Status-dependent benefit and narrow range. The Lancet review reports that supplements may add risk of type 2 diabetes in people with adequate intake and that status follows a U-shaped link with health [1]. The amount tier, the label advice and the target market are reviewed with this in mind.
Elemental selenium on the label. The label amount is the weight of selenium, not of the compound. The specification states the selenium assay of the premix, and finished units are assayed as elemental selenium.

Customization Options

Brands adjust the amount per serving, the selenium form, the format and the add-ons.

ParameterRangeNote
Amount per serving50, 70, 100 or 200 mcgOptions for the brand; premix weight per unit scales with the tier
Selenium formSelenomethionine, sodium selenite or selenium yeastSelenium percent and label wording differ by form
FormatCapsule or tabletLiquid and gummy are separate projects
Pack size30 to 120 unitsSet by the brand
Add-onsVitamin E, zinc, iodineA second active reshapes the premix weight and the uniformity check

The pilot run confirms blend uniformity of the selenium premix, capsule fill weight and tablet hardness, and the content assay of elemental selenium in the first units against the labeled 200 mcg.

Technical Status & Data Sources

ItemStatusDetails
Reference formulaNIH DSLDThe ingredient and amount come from a labeled product in the NIH DSLD (200 mcg on the label of CF000274; example DSLD labels 1808, 7231, 7234). The label names the ingredient as selenium; selenomethionine is set as the form.
SpecificationSet in formulationL-selenomethionine premix, 200 mcg elemental selenium per serving; assay, premix dilution and limits and method are fixed with the supplier. Unit size, fill weight and stability are set in formulation.
Data sourceNIH DSLDDSLD v9.4.0, downloaded 2026-01-10: 50,824 reference formulas merged from on-market labels with complete ingredient amounts. Counts show how labels are distributed.
Market reviewPer marketDose limits, labeling and claims are reviewed for each sales market before a finished product is developed.
ReferencesSources[1] Rayman MP. Selenium and human health. Lancet. 2012;379(9822):1256-68. DOI61452-9) · PubMed

Related products

OEM/ODM Development Inquiry

Essencefield supports custom supplement formulation and OEM/ODM development, including ingredient selection, dosage adjustments, delivery formats, flavors, packaging, and commercial supply. Submit your project requirements below to explore customization options, sample development, and manufacturing solutions tailored to your brand and target market.