Bespoke iron supplement manufacturing
British VitaTech is an iron supplement manufacturer that develops and makes custom iron supplements for brands worldwide, from formulation to finished product, and the brand owns the formula.
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Iron in four forms, for women's, prenatal and GLP-1 formulas
Custom iron supplements for premium brands go from the first formula to the finished product with us as their iron supplement manufacturer: capsules, tablets, gummies, liquids and powders, all made in the UK. We build iron into single-nutrient products and into women's, prenatal and GLP-1 companion formulas, with the form chosen for taste, tolerance and format. Most of our iron formulas sit between 2.1 mg a day, enough for iron's authorised claims, and the NHS's 17 mg. Accredited partner laboratories test every batch for elemental iron against the declared value, and you own the formula, its specification and test plan.
Iron sits within our women's health supplement manufacturing range. That range also covers menopause and intimate health formulas. A joint advisory from four US medical and nutrition societies names iron among the nutrients of concern for people using GLP-1 medicines (Mozaffarian and colleagues, 2025), a market our GLP-1 support supplement manufacturing serves. In the US, the Daily Value for iron rises from 18 mg for adults to 27 mg in pregnancy and lactation, the ground our prenatal and fertility supplement manufacturing covers. In the EU, national maximum amounts apply where member states have set them, and our regulation watch page covers maximum levels for vitamins and minerals.
Four forms cover most briefs, and as of October 2026 all four are on Great Britain's list of permitted forms and on the EU's. The iron content and absorption figures come from the WHO and FAO guidelines on food fortification (WHO and FAO, 2006).
| Form | Iron content | Absorption against ferrous sulphate | Where it fits |
|---|---|---|---|
| Ferrous bisglycinate | About 20% | Higher; two to three times better when a meal is high in phytate | Capsules, gummies and liquids led by taste and tolerance |
| Ferrous fumarate | About 33% | Equal | Compact tablets and capsules |
| Ferrous sulphate | 20% hydrated, 33% dried | The reference form | Capsules and coated tablets |
| Ferric pyrophosphate | About 25% | 21% to 74% of the reference | Powders and drink mixes, where it causes fewer off-colours |
Ferrous bisglycinate is a chelate, iron bound to two molecules of the amino acid glycine. In a 2023 meta-analysis of 17 randomised trials, it gave higher haemoglobin concentrations in pregnant women and fewer reported gastrointestinal adverse events than other iron supplements, although the trials varied widely (Fischer and colleagues, 2023). Ferrous iron is more soluble than ferric iron and so more bioavailable (NIH Office of Dietary Supplements, 2025), which is why ferric pyrophosphate earns its place through taste and colour rather than absorption.
Labels declare elemental iron, so the weight of the compound follows the form: 14 mg of iron takes about 70 mg of ferrous bisglycinate but about 42 mg of ferrous fumarate. Two newer forms, iron hydroxide adipate tartrate and iron milk caseinate, are permitted in the EU but not in Great Britain, so a product for both markets uses a form both lists permit.
Boxed warnings, child-resistant closures and seven iron claims
As of October 2026, iron carries seven authorised function claims on the GB nutrition and health claims register and the EU register, each needing only a source of iron:
- "Iron contributes to normal cognitive function"
- "Iron contributes to normal energy-yielding metabolism"
- "Iron contributes to normal formation of red blood cells and haemoglobin"
- "Iron contributes to normal oxygen transport in the body"
- "Iron contributes to the normal function of the immune system"
- "Iron contributes to the reduction of tiredness and fatigue"
- "Iron has a role in the process of cell division"
Products for children can also carry "Iron contributes to normal cognitive development of children". Wording such as "gentle on the stomach" implies a health benefit no claim authorises, so it stays off the label.
In the US, structure and function claims need scientific substantiation, notification to FDA and FDA's standard disclaimer. FDA's boxed accidental overdose warning is required on iron supplements in any solid oral dosage form, so tablets, capsules and gummies carry it; liquids and powders are outside the rule. Packs holding 250 mg or more of elemental iron in total, however small each dose, need child-resistant packaging, with powders of no more than 0.12% iron exempt: a bottle of 60 gummies at 5 mg each holds 300 mg, so it takes a child-resistant closure.
Hepcidin, vitamin C and the metallic taste of iron
Dose: from the claim threshold to the safety limits
Iron's authorised claims need at least a source of iron, which we set at 15% of the 14 mg reference value per daily dose: 2.1 mg. The ceiling comes from safety. The NHS says 17 mg or less a day of iron from supplements is unlikely to cause any harm. EFSA set a safe level of intake of 40 mg a day for adults, as the data could not support an upper level (EFSA, 2024), and the US Tolerable Upper Intake Level for adults is 45 mg a day (NIH Office of Dietary Supplements, 2025). We design most iron formulas between 2.1 mg and the NHS's 17 mg, and set any higher dose against the rules of each market.
Iron content doesn't fall over shelf life, so iron needs no stability overage, only a small margin. European Commission guidance accepts minerals in food supplements from 20% below to 45% above the declared value, and US rules require at least the declared amount, so we target just above the label value for every market.
Vitamin C, calcium and every-other-day dosing
Vitamin C enhances the absorption of non-haem iron, an effect the register authorises as "Vitamin C increases iron absorption" for a product that is at least a source of vitamin C, 12 mg a day. Calcium taken in the same dose can reduce iron absorption, and phytates and polyphenols in a meal reduce it too. So we pair iron with vitamin C, and keep it apart from high-dose calcium with bilayer tablets or separate servings.
Timing matters as much as form. A higher dose of iron raises hepcidin, the hormone that controls iron absorption. In two randomised trials in women with low iron stores, iron given every other day was absorbed better than the same number of doses given daily, and splitting a dose in two raised hepcidin without improving absorption (Stoffel and colleagues, 2017). We build single-dose units and pack counts around the directions the brand chooses.
The clearest probiotic data on iron absorption come from one strain. In two small single-blind isotope studies in women of reproductive age, capsules of dried Lactiplantibacillus plantarum 299v, at 10 billion CFU, raised iron absorption from a breakfast meal from 17.4% to 22.4% and from 20.9% to 24.5% (Hoppe and colleagues, 2017). We build iron and strain combinations with viable counts tested at release and through shelf life. No claim about iron absorption is authorised for any strain, and GB advertising rules and the European Commission regard the word "probiotic" itself as a health claim, so the label names the strain and carries iron's own claims.
Stability and reactivity
Ferrous salts oxidise to ferric iron in moist air and in solution, iron speeds the oxidation of vitamin C, and soluble iron compounds can make fats rancid (WHO and FAO, 2006). Dissolved iron also darkens drinks that carry tea or fruit polyphenols. Iron salts taste metallic, partly through smell: the intensity of ferrous sulphate fell when tasters' noses were blocked (Lawless and colleagues, 2005). So we keep iron dry and sealed, use coated grades of vitamin C beside it, put oils such as DHA in a separate softgel, and flush liquids with nitrogen.
Liquids need the most flavour work, capsules the least
- Capsules carry any of the four forms with no taste work, and are GMP certified. Tablets, made in-house, suit ferrous fumarate's density, and a film coat hides taste and colour. See capsule and tablet manufacturing.
- Gummies suit ferrous bisglycinate at modest doses, and are GMP certified, with an active assay on every batch. Iron tastes metallic and speeds the oxidation of vitamin C in the same piece, so it goes through our flavour development and taste masking work or into a companion capsule. See gummy manufacturing.
- Liquids and shots deliver a measured dose and are GMP certified. Dissolved iron tastes at full strength, so liquids need the most flavour work, with nitrogen flushing and oxygen-barrier packs. See liquid supplement manufacturing.
- Powders and stick packs carry ferric pyrophosphate in drink mixes and multinutrient blends, and are made in-house.
- Multinutrient formulas put iron beside vitamin C, folate and vitamin B12 in women's, prenatal and GLP-1 companion products, with calcium kept apart.
How an iron supplement manufacturer keeps iron and calcium apart
- Specification. We set the iron form, grade, particle size and elemental iron content, with limits for each, and the forms of the companion nutrients.
- Goods-in. Every supplier passes our approval process, and materials stay in quarantine until their identity and certificates of analysis match the specification.
- Weighing and pre-blending. Iron is weighed against the batch record and, in multinutrient formulas, pre-blended with part of the filler so each unit carries the same dose.
- Blending. The full blend runs to a set time, with uniformity checks before filling or compression.
- Filling or compression. Capsules are filled with in-run weight checks. Tablets are compressed and checked for weight, thickness, breaking force, friability and disintegration, and bilayer tablets keep iron and calcium in separate layers.
- Coating. A film coat masks taste, protects against moisture and gives the tablet its colour.
- Packing and labelling. Bottles are sealed with desiccant, US packs holding 250 mg or more of elemental iron in total take child-resistant closures, and labels are verified on every batch, the critical control point (CCP-01) in our HACCP plan.
The critical steps are dose uniformity, separation of iron from the nutrients it reacts with, and the right label and closure for each market. Gummies and liquids follow their own routes, with iron added late to the gummy mass and liquids compounded under nitrogen. Each product type has its own HACCP study, reviewed every year.
Elemental iron against the label, ferrous iron where form matters
Ask for the certificate of analysis behind the iron value on your label. Every batch is tested by accredited partner laboratories (ISO/IEC 17025), and batch testing is part of every order, as our testing and batch release page explains.
- Iron content: elemental iron by ICP-OES or ICP-MS against the declared value, and ferrous iron by titration where the form matters.
- Companion nutrients: vitamin C and B vitamins by HPLC, and viable counts by plate count for strain combinations.
- Contaminants: lead, cadmium and mercury by ICP-MS against the EU limits for food supplements.
- Performance: disintegration for tablets and capsules.
- Microbiology: total viable count, yeasts and moulds, and pathogens, with water activity for gummies.
- Stability: real-time and accelerated studies on every new formula, tracking vitamin C, colour, taste and oxidation to the end of shelf life.
Quality control releases every batch against its specification, and nothing is dispatched without quality control sign-off. We keep three retained samples per batch for shelf life plus one year, and a full mock recall, forward and backward with mass balance, runs in seconds. We make every format in our UK facility, which is ISO 9001, HACCP and GMP certified by BSI, and FDA registered. BRCGS implementation under way, certification expected in early 2027. R&D is a paid stage that can be included with an order of the right size. Your formula is yours, including its specification and test plan. Start your project with your iron form, format and markets.
References: WHO and FAO, Guidelines on food fortification with micronutrients (2006); Commission Regulation (EU) No 432/2012 (2012); The Nutrition (Amendment etc.) (EU Exit) Regulations 2019, Schedule 2 (2026); EFSA, overview of tolerable upper intake levels (2025); Fischer and colleagues, Nutrition Reviews (2023); Stoffel and colleagues, Lancet Haematology (2017); Hoppe and colleagues, PLoS ONE (2017); US Code of Federal Regulations, 21 CFR 101.17 and 16 CFR 1700.14 (2026).
Where it can be sold
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UK
PermittedAs of October 2026, Great Britain permits 17 iron forms in food supplements, including ferrous bisglycinate, ferrous fumarate, ferrous sulphate and ferric pyrophosphate.
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EU
Permitted with conditionsAs of October 2026, the EU permits 19 iron forms in food supplements, and national maximum amounts apply where member states have set them.
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US
Permitted with conditionsAs of October 2026, iron supplements in any solid oral dosage form, gummies included, carry FDA's boxed accidental overdose warning, and packs holding 250 mg or more of elemental iron in total need child-resistant packaging.
Where this is going
To 2030
Up: GLP-1 users and women's iron needs keep gentle iron growing
To 2036
Up, with EU dose ceilings shaping formats
What to watch
EU-wide maximum levels for minerals, once adopted, could cap iron doses in EU products
Questions brands ask
What does an iron supplement manufacturer do?
An iron supplement manufacturer develops and produces iron supplements for brands, from formulation to finished product. At British VitaTech that means choosing the iron form for taste, tolerance and format, setting the dose between the claim threshold and the safety limits, masking iron's metallic taste in gummies and liquids, and preparing labels and packs for the UK, EU and US. We make iron capsules, tablets, gummies, liquids and powders in-house, and the brand owns the formula.
Which form of iron should a supplement use?
The form follows the format and the brief. Ferrous bisglycinate suits capsules, gummies and liquids where taste and tolerance lead; ferrous fumarate packs about 33% iron into compact tablets; ferrous sulphate is the reference form; and ferric pyrophosphate causes fewer off-colours in powders and drink mixes, though it is absorbed less well. As of October 2026, all four are permitted in GB and the EU, and we confirm the form against each market's list.
How much iron should an iron supplement contain?
Enough for the claim and inside the safety limits. As of October 2026, the GB and EU claims need at least 2.1 mg of iron in the daily dose. The NHS says 17 mg or less a day from supplements is unlikely to cause any harm, EFSA set a safe level of intake of 40 mg a day for adults, and the US upper level for adults is 45 mg. US labels declare iron against a Daily Value of 18 mg for adults.
Can you make iron gummies and liquid iron?
Yes, with taste work built in from the first bench sample. Iron tastes metallic, partly through smell, and speeds the oxidation of vitamin C, so gummies use ferrous bisglycinate at modest doses, a masking flavour system and an active assay on every batch, and some brands move the iron into a companion capsule. Liquids need the most flavour work and protection from oxygen. Gummies and liquids are made in the UK and are GMP certified.
What do US iron supplements need on the label and pack?
Two things beyond a standard Supplement Facts panel, as of October 2026. FDA's boxed accidental overdose warning is required on iron supplements in any solid oral dosage form, tablets, capsules and gummies included; liquids and powders are outside the rule. Packs holding 250 mg or more of elemental iron in total need child-resistant packaging, however small each dose, so a bottle of 60 gummies at 5 mg each takes a child-resistant closure. Structure and function claims carry FDA's standard disclaimer.
Can probiotics improve iron absorption?
The clearest human data come from one strain. In two small isotope studies in women of reproductive age, capsules of Lactiplantibacillus plantarum 299v raised iron absorption from a breakfast meal, from 17.4% to 22.4% and from 20.9% to 24.5%. We build iron and strain combinations with viable counts tested at release and through shelf life. As of October 2026, no claim about iron absorption is authorised for any strain in GB or the EU, so the label carries iron's own claims.
Which claims can an iron supplement make in the UK and EU?
Seven authorised function claims, as of October 2026, each for a product that is at least a source of iron, 2.1 mg in the daily dose. They include "Iron contributes to the reduction of tiredness and fatigue", and children's products can also carry "Iron contributes to normal cognitive development of children". Adding at least 12 mg of vitamin C a day allows "Vitamin C increases iron absorption". Wording such as "gentle on the stomach" stays off the label.