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Hyaluronic acid · Weak evidence
What oral hyaluronic acid is for
The short answer. Hyaluronic acid is a real molecule in the body, abundant in skin and in joint fluid. The problem with the oral supplement is the usual one: being inside the body does not mean swallowing it puts it back where it is needed. There is a twelve-week trial with 120 mg a day where the high molecular weight group improved wrinkles versus placebo, and a review gathering trials on knee pain with favourable results. They are small studies, many of them conducted in Japan and linked to manufacturers, and that needs saying alongside the data.
Reviews find no consistent effect. It is listed because it sells, not because it works. No figure on this page is attributed to a specific product: the effect belongs to the ingredient and every number carries its source next to it.
01 What it does and how much
Each row is a measured effect, with the figure the study gives and the source number. Where the evidence gives no figure, the column says so instead of making up a percentage.
| Effect | How much | Detail |
|---|---|---|
| Crow’s feet wrinkles | improvement at 8 weeks | With 120 mg a day, the 300 kDa hyaluronic acid group showed significantly fewer wrinkles than placebo from week 8. Sixty subjects split into three groups: about twenty per group. [1] |
| Skin radiance and suppleness | improvement in all groups | At 12 weeks they improved from baseline in all groups, placebo included. This is the part of the trial worth reading carefully: improving versus yourself is not improving versus placebo. [1] |
| Knee pain | favourable results | The review gathers double-blind, placebo-controlled randomised trials on knee pain, synovial effusion or inflammation and knee muscle strength. It is a narrative review, not a meta-analysis with a pooled figure. [2] |
| Molecular weight | 2 kDa and 300 kDa | Both were tested and the 300 kDa one was the one that separated from placebo on wrinkles. Almost no label on the market states molecular weight, so you can almost never tell whether the tub resembles the one in the trial. [1] |
02 How to take it
- Dose. 120 mg a day, the dose from the skin trial.
- When. No time of day is backed. In the trial it was taken daily.
- How long before you notice it. 8 weeks for the difference versus placebo on wrinkles; the trial lasted 12.
Details that change the result
- Hyaluronic acid injected into the joint or skin is something else, with other evidence and another context: those are medical procedures, not a tub.
- Almost no product states molecular weight, which is precisely the variable that separated the groups in the wrinkle trial.
- The trials are small and much of the evidence comes from groups linked to Japanese manufacturers. That does not invalidate the data, but it changes how it is read.
- It is often sold together with collagen. Hydrolysed collagen has its own broader evidence for joint pain; if that is the goal, collagen is the better-supported bet.
03 When it makes sense and when it does not
Worth it if
- If you want to try it for skin, at 120 mg a day and allowing at least eight weeks before judging.
- With the molecular weight stated on the label, the only thing that lets it resemble the trial.
Not worth it if
- Expecting the effect of an injection: oral and injected routes are not comparable.
- As a treatment for osteoarthritis, which is a medical diagnosis.
- Before covering hydrolysed collagen, if the goal is joints, or protein and creatine, if the goal is training.
04 Sources
Every figure above comes from here. They are position stands from scientific societies, meta-analyses and peer-reviewed reviews: if a claim cannot hang from one of these lines, it is not on the page. References are cited in their original form.
- Oe M et al. Oral hyaluronan relieves wrinkles: a double-blinded, placebo-controlled study over a 12-week period. Clin Cosmet Investig Dermatol. 2017;10:267-273. Sesenta sujetos japoneses de 22 a 59 anos con patas de gallo, 120 mg/dia de hialuronico de 2 kDa o 300 kDa frente a placebo durante 12 semanas: el grupo de 300 kDa mostro arrugas significativamente menores que placebo a partir de las 8 semanas. doi:10.2147/CCID.S141845
- Oe M, Mitsugi K, Odanaka W et al. Oral hyaluronan relieves knee pain: a review. Nutr J. 2016;15:11. Revision de ensayos aleatorizados, doble ciego y controlados con placebo realizados entre 2008 y 2015 sobre dolor de rodilla, derrame o inflamacion sinovial y fuerza muscular de la rodilla. doi:10.1186/s12937-016-0128-2
This is not medical advice. It is what some studies say about an ingredient, not a protocol for you. With an illness, medication or pregnancy involved, the decision belongs to a healthcare professional who knows you.
Questions about hyaluronic acid
Answered with the data on this page
- Does oral hyaluronic acid reach the skin?
- That is the key question and it is not settled. What exists is a 12-week trial with 120 mg a day where the high molecular weight group showed fewer wrinkles than placebo from week 8, and a review describing binding to intestinal epithelial receptors as a proposed route. With about twenty subjects per group, it is a signal, not a certainty.
- Does it help with knee pain?
- The available review gathers placebo-controlled randomised trials with favourable results on knee pain and synovitis symptoms. It is a narrative review and the studies are small. If the goal is joints, hydrolysed collagen has a broader body of evidence.
- What dose of hyaluronic acid should you take?
- 120 mg a day is the dose from the skin trial, maintained for 12 weeks. Beyond that figure, each product uses whatever it wants.
- Is it the same as injected hyaluronic acid?
- No. Joint injections and dermal fillers are medical procedures with their own evidence, and they cannot be used to back what a capsule does. They are two different things with the same name on the label.
And now, which to buy
Prices, kept apart from the evidence
This page explains what hyaluronic acid does and deliberately names no brand. The comparison is the other half: 24 products from 4 stores from €0.105 per capsule, sorted by price and by how verifiable their certification is.
Other guides
What each supplement does, with its sources