Eggshell membrane is the thin protein layer lining the inside of an eggshell, and it has moved from food-industry by-product to a joint-support ingredient in its own right. Brands abroad ask for it as an alternative to glucosamine and chondroitin, often at a lower daily dose.
This guide is for brand owners planning an eggshell membrane product made in Japan. It covers what the human trials show, the difference between natural and hydrolysed forms, the allergen consideration, and what to fix before asking for a quotation.
Health supplements are foods, not medicines, and are not a substitute for medical treatment. Nothing here is a claim that any product prevents, treats or cures a disease.
💬 Planning an eggshell membrane product made in Japan? We check the full formula against Japanese food law first. See Japan-made supplement OEM.
What the research shows
Small randomised trials of eggshell membrane in people with knee osteoarthritis report better scores than placebo on some pain and stiffness measures, but not on every main outcome, so the evidence is mixed.
| Study | Design | Reported result |
|---|---|---|
| Randomised, multicentre, double-blind, placebo-controlled trial, Clinical Rheumatology 2009;28(8):907–914 (PMID 19340512) | 67 adults with knee osteoarthritis (34 eggshell membrane, 33 placebo); natural eggshell membrane 500 mg/day for 8 weeks | Pain and stiffness subscores improved significantly versus placebo at days 10, 30 and 60; the function subscore and the overall score did not differ significantly from placebo |
| Randomised, double-blind, placebo-controlled trial, Journal of Medicinal Food 2021;24(3):292–298 (PMID 32633648) | 150 adults aged 40–75 with knee osteoarthritis; natural eggshell membrane 300 mg/day for 12 weeks | The primary outcome, a 0–10 pain rating at week 6, fell at about the same rate in both groups; two secondary knee questionnaire scores (pain and daily-life function) improved significantly versus placebo from week 1 |
| Randomised, double-blind, placebo-controlled trial, Journal of Medicinal Food 2019;22(9):875–884 (PMID 31381494) | 88 adults with knee osteoarthritis; hydrolysed (water-soluble) eggshell membrane 450 mg/day for 12 weeks | In the standard analysis there was no statistically significant difference from placebo on the joint questionnaire, the six-minute walk or knee range of motion; only an analysis adjusted for each person’s starting score showed less stiffness by day 5 and better walking results |
Four points to keep in view:
- Size. All three trials are single studies with modest sample sizes; none has been independently replicated at the same dose and form.
- Mixed result. No trial was positive on every main outcome. The 2009 trial found no difference on function or the overall score, the 2021 trial found no difference on its primary pain rating, and the 2019 trial found differences only in the adjusted analysis. Report these alongside the positive results, not instead of them.
- Funding. All three trials were funded by companies. In the 2009 and 2019 trials the sponsor supplied the eggshell membrane ingredient tested, and study authors were employed by or consulted for the sponsor. The 2021 trial was funded by a company whose role in supplying the ingredient is not stated. Read the funding line of any study you plan to cite.
- Population. All three trials studied adults with diagnosed knee osteoarthritis. That is a fact about the research population, not something to carry into a product claim.
Checked against the published abstracts on 13 October 2026.
Natural or hydrolysed eggshell membrane
Natural (minimally processed) and hydrolysed (water-soluble) eggshell membrane are different preparations, and a trial on one cannot stand in for the other.
| Natural eggshell membrane | Hydrolysed eggshell membrane | |
|---|---|---|
| Processing | Minimally processed, whole-membrane powder | Broken down into smaller, water-soluble fragments |
| Trial doses seen | 300–500 mg/day | 450 mg/day |
| Trial result seen | Some pain, stiffness and daily-life scores improved versus placebo in both trials reviewed; function, overall and primary pain-rating scores did not | No significant difference from placebo in the standard analysis; differences only after adjusting for starting scores |
| Formulation | Capsule; less soluble | Capsule or powder; dissolves more readily |
Treat the two as separate ingredients with separate evidence. A study on one form is not evidence for the other.
Eggshell membrane and egg allergy
Eggshell membrane is derived from eggs and must be treated as an egg allergen for labelling purposes, even after processing.
Egg is recognised as a major food allergen in the main regulatory systems brands sell into, and eggshell membrane and its hydrolysates retain that allergen status because of their source, regardless of how the membrane is processed. Confirm your market’s allergen labelling requirement for egg before finalising packaging, and disclose the egg source on the ingredient list.
💬 Need an evidence summary for your regulatory adviser that includes the allergen point? We prepare it with the manufacturing documents. Tell us your market.
What Japanese products say
Eggshell membrane is an established food ingredient in Japan, and functions supported by adequate evidence can be notified under the Foods with Function Claims system on a product-by-product basis.
As with any ingredient under this system, the business that notifies the product is responsible for the scientific evidence behind the stated function, and submits it to the Consumer Affairs Agency before sale. Confirm the notified wording of any specific product you reference, since it is set individually rather than for the ingredient as a whole.
Wording that stays on safe ground
Describe eggshell membrane by the form, dose and outcome studied, never by a disease it would treat.
| Safer wording | Wording to avoid |
|---|---|
| ”Studied for knee joint comfort and stiffness” | Names of joint diseases, or “treats” or “reverses” arthritis |
| ”Contains 500 mg natural eggshell membrane per serving" | "Clinically proven” without naming the study and its limits |
| ”Contains egg (eggshell membrane)” on the allergen declaration | Omitting the egg allergen disclosure |
How eggshell membrane is formulated
Trial doses of 300–500 mg a day fit comfortably in a single daily capsule.
| Dosage form | Why brands choose it | What to weigh up |
|---|---|---|
| Hard capsule | Matches trial doses in a single daily serving | Simplest match to the published trials |
| Powder blend | Suits the more soluble hydrolysed form | Taste and dissolving |
Decisions that shape the specification:
- Form. Choose natural or hydrolysed eggshell membrane deliberately, and cite only the trials that match the form you use.
- Amount per serving. Match the amount to the study you intend to cite — for example 500 mg/day for the 2009 natural-form trial, or 300 mg/day for the 2021 trial.
- Allergen declaration. Confirm the egg allergen statement required in each market you sell into.
- Companion ingredients. Eggshell membrane is sometimes combined with glucosamine, chondroitin or collagen in joint formulas. Every ingredient needs its own check against Japanese food law.
The check that comes first
Every ingredient must be permitted in foods in Japan, or a Japanese factory cannot make the product.
Eggshell membrane itself is established in Japanese foods. Companion ingredients in a combined joint formula are where a check most often turns up a problem. See the Japan-made supplement OEM page, and compare with our glucosamine and chondroitin guides if you plan a combined formula.
Before you ask for a quotation
A factory can quote accurately once the form, the amount, the companions and the packaging are fixed.
- Natural or hydrolysed eggshell membrane, and the amount per serving
- Dosage form
- Companion ingredients and their amounts
- Allergen declaration requirements in your markets
- Packaging
- Countries you will sell in, and first order and annual volume
💬 Ready to design a Japan-made eggshell membrane product? Send us the concept — form, amount, companion ingredients and the countries you will sell in.
Frequently asked questions
1. Does eggshell membrane help with knee joints?
The evidence is mixed. Two small trials of natural eggshell membrane in adults with knee osteoarthritis found better pain or stiffness scores than placebo on some measures, but not on function, the overall score or one trial’s primary pain rating. A trial of the hydrolysed form found no difference in its standard analysis. Describe eggshell membrane as studied for knee joint comfort and stiffness.
2. Is natural eggshell membrane the same as hydrolysed eggshell membrane?
No. They are different preparations with separate trial evidence. A study on one form should not be presented as evidence for the other.
3. Is eggshell membrane an allergen?
Yes. It is derived from eggs and must be declared as an egg allergen on the label, regardless of processing.
4. What dose do trials use?
300–500 mg a day for natural eggshell membrane, and 450 mg a day in the hydrolysed-form trial reviewed here.
5. Who funds eggshell membrane research?
Companies, in all three trials reviewed here, and in two of them the company supplied the ingredient tested. Check the funding statement of any study you cite.
Sources: “Eggshell membrane in the treatment of pain and stiffness from osteoarthritis of the knee: a randomized, multicenter, double-blind, placebo-controlled clinical study”, Clinical Rheumatology 2009;28(8):907–914 (PMID 19340512); “Mildly Processed Natural Eggshell Membrane Alleviates Joint Pain Associated with Osteoarthritis of the Knee: A Randomized Double-Blind Placebo-Controlled Study”, Journal of Medicinal Food 2021;24(3):292–298 (PMID 32633648); “A Randomized, Double-Blind, Placebo-Controlled, Prospective Clinical Trial Evaluating Water-Soluble Chicken Eggshell Membrane for Improvement in Joint Health in Adults with Knee Osteoarthritis”, Journal of Medicinal Food 2019;22(9):875–884 (PMID 31381494); Consumer Affairs Agency notifications for Foods with Function Claims. Checked on 13 October 2026.