Vitamin D3
Compiled from published pharmacological and botanical literature. Not independently verified by Herbuno. Spotted an error or have a correction? Flag it below →
| Compound | Vitamin D3 (cholecalciferol) |
|---|---|
| Chemical class | Secosteroid — 9,10-secocholesta-5,7,10(19)-trien-3β-ol |
| CAS | 67-97-0 |
| Primary source | Lichen (Cladonia rangiferina and related species) for vegan grades; lanolin from sheep wool for conventional grades |
| Key applications | Bone mineralisation, calcium homeostasis, immune modulation, muscle function |
| Claim strength | High for deficiency correction and bone health; null for cancer and cardiovascular prevention in replete populations |
| Typical form | Oil-dispersible resin, cold-water-dispersible powder (100,000 IU/g), or liposomal powder |
| Buy from Herbuno | Vitamin D3 100,000 IU/g from Lichen · Liposomal Vitamin D3 · Liposomal Vitamin K2 + D3 |
| Origin | Processed / Sourced from India |
| MOQ | R&D 100 g / 250 g (subject to stock) · Pilot batch 1–5 kg · Bulk 10 kg, 25 kg and above |
| Lead Time | Dispatch within 72 hrs from stock · fresh-batch production (typically 50 kg+): 10 working days |
| Documentation | CoA & MSDS standard with every lot; phytosanitary on request |
Name origin: The vitamins were lettered in order of discovery, and by the time the anti-rachitic factor was isolated in 1922 the letters A, B and C were taken. It was named D by Edward Mellanby's contemporary Elmer McCollum. The "3" distinguishes cholecalciferol, the animal and lichen form, from ergocalciferol or D2, which comes from irradiated fungal ergosterol. Strictly it is not a vitamin at all but a prohormone, since humans synthesise it in skin from 7-dehydrocholesterol under UVB.
Traditional use: The therapeutic history begins with cod liver oil, used in northern Europe from the eighteenth century for what was then called the English disease. Rickets became endemic in industrial cities as coal smoke cut UVB at street level and children worked indoors — a deficiency disease created by industrialisation and cured, before anyone understood why, by a fish oil and by sunlight. Sanatorium heliotherapy in the Alps rested on the same unrecognised mechanism.
Research trajectory: Structural elucidation in the 1930s led to fortification of milk and the near-elimination of rickets in fortifying countries. The modern era began when assays for serum 25-hydroxyvitamin D allowed population status to be measured, revealing widespread insufficiency and prompting two decades of trials testing whether raising that marker improved outcomes beyond bone. The results have been sobering: supplementation reliably raises 25(OH)D and reliably helps the deficient, but large trials in replete populations have mostly come back null. That gap between biomarker and outcome is the defining finding of recent vitamin D research.
Commercial source: Conventional D3 is made from lanolin, where 7-dehydrocholesterol is extracted from wool grease and converted photochemically. Vegan D3 uses lichen, which accumulates the same provitamin; the lichen is harvested, extracted and the provitamin irradiated by the identical route. The finished molecule is cholecalciferol in both cases — structurally indistinguishable. Lichen supply is the constraint: it is slow-growing and largely wild-harvested, which makes vegan D3 several times the price of lanolin D3 and makes supply continuity a real procurement question rather than a formality.
Evidence for Vitamin D3 Applications
D3 is meaningfully more effective than D2 at raising and sustaining serum 25-hydroxyvitamin D, and this is one of the few form comparisons in the nutrient space with a clean randomised answer. A single-blind trial in 33 healthy adults given 50,000 IU weekly of each calciferol for 12 weeks found D3 roughly 87% more potent by area under the 25(OH)D curve, with the separation widening over time as D2 cleared faster. [Armas 2011] For a formulator the implication is direct: D2 and D3 are not interchangeable on an IU-for-IU basis despite both being declared in international units, and a vegan product using D2 to avoid lanolin is accepting a real potency penalty when lichen D3 exists. Claim strength: High.
Deficiency correction and bone outcomes are where the evidence is strongest. In populations with low baseline status, supplementation restores calcium absorption, suppresses the compensatory parathyroid hormone elevation, and improves bone mineral density; in children, correction prevents and reverses rickets. Combined calcium and vitamin D supplementation in institutionalised older adults with low intakes has shown fracture reduction. These effects depend on a deficient starting point, which is the recurring theme of the whole literature. Claim strength: High.
The large prevention trials in replete populations have been null, and a formulator should know this rather than discover it from a regulator. VITAL randomised more than 25,000 US adults to 2,000 IU/day of vitamin D3 or placebo and found no reduction in invasive cancer incidence or major cardiovascular events over roughly five years. Trials of vitamin D for respiratory infection, depression, cognitive decline and type 2 diabetes prevention have produced a similar pattern: biomarker moves, outcome does not. The honest reading is that vitamin D corrects a deficiency state rather than acting as a general-purpose preventive. Claim strength: High for the null result.
Lichen-derived and lanolin-derived D3 are the same molecule, and the case for equivalence rests on molecular identity rather than on a comparative trial. This distinction matters. There is no published head-to-head human bioavailability study establishing that lichen D3 raises 25(OH)D identically to lanolin D3 at matched IU; the equivalence argument is chemical, not clinical. That argument is strong — cholecalciferol is cholecalciferol, and the specification is an IU assay rather than a botanical marker — but it should be stated as molecular identity and not dressed up as trial evidence. Claim strength: High on identity, Emerging on comparative clinical data.
Vitamin D is fat-soluble and stored, so toxicity is possible in a way it is not for water- soluble vitamins, though it requires sustained very high intake. Hypercalcaemia with its renal and cardiovascular consequences is the mechanism. The EU and US tolerable upper intake level for adults is 4,000 IU/day; reported toxicity generally involves intakes well above that maintained for months, frequently from dosing errors in concentrated liquids. The practical formulation risk is not the declared dose but the concentrate: a 100,000 IU/g powder is a material where weighing error at the blending stage translates directly into overdose. Claim strength: High.
Co-formulation with vitamin K2 is widely marketed on the rationale that D3 increases calcium absorption while K2 directs its deposition into bone rather than vasculature. The mechanistic logic is coherent and K2-dependent proteins including osteocalcin and matrix Gla protein are well characterised. Outcome trials demonstrating that the combination reduces vascular calcification or fracture more than D3 alone are limited, and the combination is better described as mechanistically rational than as clinically proven. Claim strength: Moderate.
Sourcing vitamin D3 from Herbuno. Our primary grade is lichen-derived cholecalciferol at 100,000 IU/g, suitable for vegan and vegetarian certification, with liposomal D3 and a combined liposomal K2 + D3 powder for formulators working on delivery or convenience formats.
Lichen supply is genuinely constrained and seasonal. We recommend discussing forward volumes rather than assuming spot availability on bulk quantities. All lots ship with CoA and MSDS as standard; request a quotation to confirm current lead times.
Dosage & Formulator Specification
Vitamin D3 is specified in international units, where 40 IU equals 1 microgram of cholecalciferol. Commercial material is supplied as a dilution — 100,000 IU/g is the common trade grade, equivalent to 0.25% cholecalciferol by weight, with the balance being carrier. A 1,000 IU dose therefore requires 10 mg of 100,000 IU/g powder, which is too small to dose accurately on its own and must be pre-blended. Overage is standard practice: manufacturers typically add 10–30% above label claim to cover degradation across shelf life, and the overage needs to be agreed explicitly with the supplier rather than assumed.
Adult RDA is 600 IU/day rising to 800 IU over 70 in US guidance, with EFSA setting adequate intake at 600 IU. Common supplemental doses run 1,000–2,000 IU/day; 5,000 IU products exist and sit below the 4,000 IU upper limit only if the limit is read as applying to supplemental rather than total intake, which is a position worth checking against the target market's regulator. Weekly and monthly bolus dosing is used clinically for compliance, though some trials of very large infrequent boluses have reported adverse signals on falls and fractures, so bolus formats should not be adopted purely for convenience.
Stability is the main formulation constraint. Cholecalciferol degrades on exposure to oxygen, light, heat, acid and trace metals, particularly iron and copper. Oil-dispersible grades are more stable than dry powders in general, but cold-water-dispersible beadlets with a starch or gum matrix and an antioxidant system are the practical choice for tablets, capsules and powder blends. In a multivitamin containing iron or copper the degradation rate rises sharply, which is where the overage calculation is usually underestimated. Accelerated stability testing on the actual finished matrix, not on the raw material, is the only reliable guide.
For analytical control, specify potency by HPLC with UV detection against a cholecalciferol reference standard, and require the certificate to state both the assay value and the assay date, since potency declines from the date of manufacture. Confirm the carrier system, since it determines dispersibility and compatibility with the finished format. For vegan claims require documentation of the lichen source and a statement excluding lanolin at every stage, as the two streams run through similar downstream processing. India-origin lichen-derived material ships with a phytosanitary certificate on request alongside CoA and MSDS.
Frequently Asked Questions — Vitamin D3
Is lichen vitamin D3 the same as lanolin D3?
The molecule is identical — cholecalciferol from either route is the same secosteroid, and the specification is an IU assay rather than a botanical marker. What does not exist is a published head-to-head human trial showing matched IU raise 25(OH)D identically. We rest the equivalence on molecular identity and say so, rather than implying clinical comparison data that has not been published.
Should I use D2 instead to keep the product vegan?
Not if lichen D3 is available to you. A randomised trial giving 50,000 IU weekly of each found D3 roughly 87% more potent than D2 by area under the 25(OH)D curve over 12 weeks, with D2 clearing faster. Both are declared in IU, which conceals the difference on a label. D2 remains the cheaper vegan route, but it is a potency compromise, not an equivalent swap.
Does vitamin D prevent cancer or heart disease?
No, on the available trial evidence. VITAL randomised over 25,000 adults to 2,000 IU/day or placebo and found no reduction in invasive cancer or major cardiovascular events across about five years. The same pattern — biomarker rises, outcome unchanged — recurs across respiratory infection, depression and diabetes prevention trials. Vitamin D corrects a deficiency state; it is not a general preventive.
How do I dose 100,000 IU/g material accurately?
You pre-blend. A 1,000 IU dose is 10 mg of material, which cannot be weighed reliably at production scale on its own. Build a premix with a defined carrier, confirm blend uniformity, and agree the overage with us explicitly — typically 10 to 30% above label claim depending on the matrix and the shelf life you need to hold.
What destroys vitamin D3 in a finished product?
Oxygen, light, heat, acidity and trace metals, with iron and copper the worst offenders. A multivitamin containing both iron and D3 will lose potency considerably faster than a standalone D3 product, which is where overage calculations are most often set too low. Test stability on your actual finished matrix rather than relying on raw material data.
Why source vitamin D3 from India?
Around 80% of raw nutraceutical ingredients originate in China, and a qualified second origin is increasingly a continuity requirement rather than a cost exercise. Lichen D3 adds a specific supply risk of its own, since lichen is slow-growing and largely wild-harvested. Holding an India-origin source gives you a second qualified route with a single documentation set for both the vegan and conventional streams.