Home › Contract manufacturing guide › Developing a formula

Supplement formulation: dosage, upper limits and nutrient interactions

Reviewed by Dr. Daniel Wallerstorfer, molecular biologist and founder of Novogenia · Updated: 11 October 2026 · Reading time: 10 min

How to formulate a supplement: two routes

Before you get down to milligrams, there is a basic question: do you bring a finished formula, or should the manufacturer derive one from your goal? Both are common – and both routes end up with the same review of dosage, interactions and feasibility.

Define your goal in terms of target group and need, not in terms of health promises. What you can later put on the pack depends on which health claims are authorized in the EU for the nutrients you include – and these claims usually require the nutrient to be present in at least a “significant amount”. That is why supplement formulation and marketing should be planned together from day one.

The chemical form is part of the formula, too. Folate, for example, is available as folic acid or as methylfolate. Which nutrients may be used in food supplements, and in which forms, is laid down in Directive 2002/46/EC. A good manufacturer will tell you which form it recommends and why.

The dosage window: minimum and maximum amounts

For each nutrient, you need an amount that is high enough to be meaningful and low enough to be safe. The range in between is the dosage window. What surprises many brands: EU law does not set uniform numbers for it.

• What EU law regulates: the permitted nutrients and their forms (Directive 2002/46/EC), plus the reference intakes for labeling and the 15% threshold above which an amount counts as “significant” (Regulation (EU) No 1169/2011).
• What is missing: harmonized EU-wide minimum and maximum amounts for food supplements. Article 5 of the Directive provides for them, but they have never been adopted.
• What applies anyway: individual countries have their own statutory maximum amounts. If you sell in several countries, you need to know the rules of each target market.
• The scientific ceiling: the European Food Safety Authority (EFSA) derives a Tolerable Upper Intake Level (UL) for many nutrients. It is the maximum chronic daily intake that is not expected to pose a risk of adverse health effects.

So every manufacturer has to set its own dosing rule – ask to see it. Novogenia has published the dosing window it uses for personalized formulas:

• Minimum: about one third (30–35%) of the reference intake (RDA, shown on labels as NRV) for every included nutrient – more than twice the 15% threshold of labeling law.
• Maximum: about 300% of the RDA, used only where genetics, lifestyle data or blood values justify a higher dose.
• Hard safety limit: for every nutrient with an EFSA UL, the maximum is at or below that value. National statutory maximum amounts are complied with as well.
• Without an RDA: ingredients such as omega-3, coenzyme Q10, alpha-lipoic acid, lutein, MSM or phytosterols have a fixed minimum and maximum per ingredient.

Some nutrients deliberately deviate from the basic rule. An excerpt from the published table (amounts per day, percentages relative to the RDA):

The exceptions have reasons: only about 1% of a high oral dose of vitamin B12 is absorbed (roughly 10 µg of 800 µg), so its window sits far above the RDA. For vitamin D3, the labeling reference value is 5 µg, whereas EFSA’s adequate intake for adults is 15 µg. For magnesium and zinc, the maximum equals the EFSA UL and is therefore below the basic rule. Iron (14 mg) and manganese (2.5 mg), by contrast, have a higher minimum. You can find all values under dosing limits for micronutrients.

Tip: A high number on the label is not a quality feature in itself. What matters is that every amount is justified and stays permitted in all of your target markets.

Nutrient interactions: what competes, what complements

Some nutrients use the same absorption routes in the gut and compete for them when they arrive at the same time. Others can oxidize each other. Still others are deliberately combined because they complement each other.

The traditional answer to competing nutrients is two products or two intake times – inconvenient for your customers. With microcapsules whose release is controlled per nutrient, the separation can happen within a single daily serving: one nutrient is released quickly, the other over several hours.

A Novogenia laboratory study also describes how sustained release spreads the load: because less arrives at once, according to the study it is less likely that several nutrients compete for the same transport routes in the intestinal wall. How this works, and where the limits of these data lie, is explained in Sustained-release supplements: when delayed release makes sense.

Ask your manufacturer: Which combinations in my formula are critical, and how do you solve them – by separation, by controlled release, or by dropping a nutrient?

Volume: how many nutrients fit into one daily serving?

A daily serving has limited space – whether it is a stick pack, a capsule or a scoop. How much fits depends less on the number of nutrients than on their amounts:

• Vitamins dosed in micrograms, such as vitamin B12, D3 or folate, take up hardly any space.
• Minerals such as calcium or magnesium are dosed in hundreds of milligrams – in the table above, the maximum for calcium is 1,200 mg per day. They usually determine the volume.
• The compound weighs more than the nutrient: the label states the amount of the nutrient itself, but what is processed is a compound, such as a salt of the mineral. The mass that has to fit into the serving is therefore larger than the number on the label.
• Carrier material and coatings need space as well, especially when nutrients are encapsulated separately or given a sustained-release or stomach-acid-resistant coating.

If your preferred formula doesn’t fit into one serving, there are three clean options: adjust amounts within the dosage window, prioritize nutrients, or split the daily serving into two units. In Novogenia’s personalized formulas, for example, the requirement is split across two sachets when it exceeds the volume of one. A higher nutrient concentration in the microcapsules also changes the number of capsules, but not the dose.

So clarify volume early, ideally in your brief: how much fits into the planned serving, and which nutrients drive the volume of your formula? Which format suits it best is compared in Supplement dosage forms compared.

A special case: omega-3 needs a softgel

Most vitamins and minerals are powders; omega-3 fatty acids are an oil. Manufacturers that mainly process powders therefore usually supply omega-3 in a separate format, typically a softgel.

At Novogenia, omega-3 is the only exception to the “no liquid raw materials” rule: it is supplied as a vegan softgel of 350 mg, with no more than 4 softgels per daily serving. For your formula, this means:

• The omega-3 amount follows from the number of softgels – there is no continuous dosing.
• Omega-3 has no RDA. As with other ingredients without a reference intake, a fixed minimum and maximum apply.
• Plan the softgels into volume, packaging and the recommended daily dose from the start.

Samples and the approval loop

A formula is rarely right on the first try. So plan a clear loop of proposal, review, sample and approval:

1. Brief: goal or exact formula, target markets, pack size and planned volume.
2. Formula proposal: nutrients, forms, amounts per daily serving and – where relevant – the release profile per nutrient.
3. Review: dosage window, national maximum amounts in your target markets, interactions and volume.
4. Sample: check appearance, smell, taste and handling.
5. Adjustment: send change requests back in one batch, not one at a time.
6. Written approval: the approved version is the basis for the label, the notification and production.

Every extra round takes time. At Novogenia, development takes one week to three months – fastest when all nutrients are already in stock as finished Microtransporters. If a nutrient has to be newly encapsulated, that is a development project of its own with more lead time. Which raw materials can be processed at all is covered in Which raw materials can be processed.

If one person on your side collects and approves all changes, you avoid most revision loops. And keep in mind: whoever sells the product under their own name is responsible for it and for everything on the pack – even if the manufacturer developed the formula.

Checklist for your formula

• Goal and target group are clearly defined – without health promises.
• Chemical form and amount per daily serving are set for every nutrient.
• Every amount is within the manufacturer’s dosage window and below the safety limits.
• National maximum amounts have been checked for every target market.
• Critical combinations have been identified and solved – by separation or controlled release.
• The volume fits into the planned serving.
• Special cases such as omega-3 are planned into volume and packaging.
• Your planned marketing claims match the amounts in the formula.
• All raw materials are available; new developments are built into the timeline.
• The sample has been checked and the final version approved in writing.

Frequently asked questions

Related: Dosing limits for micronutrients · How Microtransporters release nutrients · Sustained-release supplements

Note: This guide is general information and does not constitute legal advice. Regulations can change; errors and changes excepted. Always have legal questions about your specific product checked by a qualified expert.