Supplements › Chemical compound

Hyaluronic acid

A substance the body makes to hold water in skin and joint fluid. As a supplement, it is most studied for skin moisture and wrinkles, and for knee pain.

Strongest evidenceJoint comfortStrong, 299 studies
Median dose in studies90 mg a dayFrom 16 study groups
Dose in skin trials60 to 200 mg a dayFor 4 to 12 weeks.
Dose in joint studies30 to 300 mg a dayFor 4 weeks to 12 months.
Ask a doctor or pharmacist first

Ask a doctor or pharmacist first if you:

  • are pregnant or want to give it to a child: EFSA judged rooster comb extract, a source of hyaluronic acid, safe for a target group without them[1]
  • have reacted to sodium hyaluronate before, or are allergic to bird protein: rooster comb extract comes from the combs of roosters[1]
  • take medicines every day: some dietary supplements interact with prescription or non-prescription medicines[2]
  • think about hyaluronic acid injections for knee osteoarthritis: in large trials they raised the risk of serious adverse events[3]

Overview

What is hyaluronic acid?

Hyaluronic acid, also called hyaluronan, is a substance the body makes itself. It is found in all connective tissues and organs, including the skin and the fluid in joints.[4] About half of the body's hyaluronic acid is in the skin, where it keeps the tissue moist.[5] Its amount in the skin falls with age.[6]

It is used as a medicine, in cosmetics, in food and as a dietary supplement.[5] Doctors inject it into the knee for osteoarthritis[7] and into folds of the face as a filler.[8] Supplements contain hyaluronic acid made by fermentation or extracted from rooster combs.[9][1]

Does hyaluronic acid work?

Taken by mouth, it has some support for skin. A 2025 meta-analysis of 7 trials found better skin hydration, elasticity and wrinkle depth than with placebo, but no clear effect on firmness.[10]

For joints, a 2024 review found 11 studies of hyaluronic acid taken by mouth, with 597 patients in total. Of these, 9 reported less pain or better function.[11] Most joint research tested injections into the knee instead. A 2022 meta-analysis of 169 trials found that, in large trials, injections lowered pain only a little, less than patients notice.[3]

Hyaluronic acid eye drops are studied for dry eyes. A 2017 review found them about as good as other artificial tears.[12]

Is hyaluronic acid safe?

In studies, hyaluronic acid taken by mouth caused few side effects. A 2024 review of 11 joint studies, with doses of 30 to 300 mg a day, found side effects rare and mild.[11] In a 6-week trial in 61 people with dry skin, dermatologists found no side effects linked to it.[13]

EFSA judged rooster comb extract, a source of hyaluronic acid, safe at the use its maker proposed, up to 80 mg a day. The maker's target group left out pregnant women, children and people who react to sodium hyaluronate or to bird protein.[1]

Injections carry more risk. In large trials, hyaluronic acid injections into the knee raised the risk of serious adverse events by about half compared with placebo (relative risk 1.49).[3] Ask a doctor or pharmacist first if you are pregnant, are allergic to bird protein or take medicines every day.[1][2]

How it works

Hyaluronic acid, also called hyaluronan, is a sugar-based molecule of the glycosaminoglycan group.[1] The body makes it and keeps about half of it in the skin, where it keeps the tissue moist.[5] In mice, gut bacteria broke down swallowed hyaluronic acid, and only about 0.2% of it was absorbed.[14]

  1. Gut bacteria

    In mice, gut bacteria of the Bacteroides group were needed to absorb swallowed hyaluronic acid. They cut it into small pieces of less than 3 kDa.[14]

  2. Absorption

    Part of these small pieces passes through the gut wall. The rest is turned into short-chain fatty acids. In mice, only about 0.2% of a dose was absorbed.[14]

  3. Indirect effect

    Hyaluronic acid binds to receptors on the cells of the gut lining.[15] The authors of the mouse study think that hyaluronic acid or its breakdown products work through effects on the whole body, not by reaching skin and joints directly.[14]

  4. Skin

    A 2014 review reported that part of swallowed hyaluronic acid reaches the skin. There it helps the body make more hyaluronic acid and makes skin cells called fibroblasts multiply.[5]

Benefits and studies

Each row is one benefit. The square shows the grade and the number of studies. Open a row to see the most trusted studies.

StrongModerateWeakNo trials
BenefitMain effects in studiesStudiesPeople

Dose

Skin trials gave 60 to 200 mg of hyaluronic acid by mouth a day, for 4 to 12 weeks.[16][9][4] Joint studies gave 30 to 300 mg a day.[11]

Usual dose

For skin, three trials gave 120 mg a day for 6 to 12 weeks. They studied 40 healthy adults, 61 people with dry skin and 150 healthy adults.[4][13][16] The last trial also tested 60 mg a day and a placebo.[16] One trial gave 200 mg a day for 28 days.[9] For knees, one trial gave 200 mg a day for 12 months,[17] and another gave 80 mg of rooster comb extract a day in a yoghurt.[18]

Form

Trials used sodium hyaluronate of 1.8 MDa,[16] hyaluronic acid of 300 kDa or 800 kDa,[13] a mix of sizes made by fermentation,[9] or rooster comb extract.[18] Rooster comb extract also contains chondroitin sulphate and dermatan sulphate.[1]

How long

Skin moisture rose after 2 to 8 weeks in one trial and after 28 days in another.[6][9] Wrinkles improved after 8 and 12 weeks.[4] Joint studies lasted 4 weeks to 12 months.[11]

Highest dose studied

Joint studies gave up to 300 mg a day, and side effects were rare and mild.[11] EFSA judged rooster comb extract safe at the use its maker proposed: up to 80 mg a day, added to dairy foods. In rats, 600 mg per kg of body weight a day for 90 days caused no harm.[1] The target group that the maker proposed, and EFSA assessed, left out pregnant women, children and people who react to sodium hyaluronate or to bird protein.[1] They should ask a doctor or pharmacist first.[1]

Doses in studies

Most studies gave 50 to 100 mg a day, for 1 to 3 months.

The counts are study groups. A study group is one set of people in a study who took the same dose. One study can have several groups. These are amounts from studies, not advice for you.

How much a day16 groups in 14 studies
  1. Up to 10 mg1 group
  2. 10 to 25 mg0 groups
  3. 25 to 50 mg3 groups
  4. 50 to 100 mg6 groups
  5. 100 to 250 mg5 groups
  6. 250 to 500 mg1 group
For how long21 groups in 18 studies
  1. 1 week or less0 groups
  2. 1 to 4 weeks5 groups
  3. 1 to 3 months15 groups
  4. 3 to 6 months1 group
  5. 6 to 12 months0 groups
  6. More than a year0 groups
Half of the groups took less than 90 mg a day. Half took more.Half of the groups took 57.5 to 140 mg a day. A quarter took less, a quarter took more.

Taken together

10 of 21 study groups took hyaluronic acid with something else. This shows what studies gave together, not what works together.

  1. Chondroitin3 studies3
  2. Collagen3 studies3
  3. Glucosamine3 studies3
  4. Type-II Collagen3 studies3
Bars and numbers count study groups. A companion is shown only when at least 3 different studies gave it.

Protocols

What studies used when they gave hyaluronic acid for one goal, or to a group of people.

Each protocol describes what studies used, for one goal or for one group of people. It is not advice for you: talk to a doctor before you start a supplement.

Questions

10 questions in 4 groups. Open one for the short answer; each has its own page with the full answer and sources.

Basics
Are hyaluronic acid supplements the same as hyaluronic acid injections?

No. A supplement is swallowed. In mice, gut bacteria cut swallowed hyaluronic acid into small pieces, and only about 0.2% was absorbed.[14] An injection puts hyaluronic acid straight into the knee joint[7] or, as a filler, into folds of the face.[8]

Most studies of hyaluronic acid tested injections. Knee injections alone were tested in 169 trials.[3] Their results do not show what a supplement does. Supplements were tested in far fewer trials, such as the 7 skin trials of a 2025 meta-analysis.[10]

Open the answer with sources ›
How long does hyaluronic acid take to work?

In skin trials, effects appeared after 2 to 12 weeks. Skin hydration rose after 2 to 8 weeks in one trial and after 28 days in another.[6][9] Wrinkles improved after 8 and 12 weeks, and the outer skin layer became thicker after 12 weeks.[4][6]

Joint studies lasted 4 weeks to 12 months.[11] In one 12-month knee trial, a difference from placebo was seen at months 2 and 4, only in people aged 70 or younger.[17]

Open the answer with sources ›
Benefits
Do hyaluronic acid supplements improve skin?

Small trials suggest they do. A 2025 meta-analysis of 7 trials found that hyaluronic acid taken by mouth improved skin hydration, elasticity and wrinkle depth compared with placebo. It found no clear effect on firmness or on water loss through the skin.[10]

Read the full answer ›
Do hyaluronic acid supplements help knee pain?

The evidence is weak. A 2024 review found 11 studies of hyaluronic acid taken by mouth, with 597 patients in total, most with osteoarthritis. Of these, 9 reported less pain or better joint function.[11] In a 12-month placebo-controlled knee trial, a clear benefit was seen only in people aged 70 or younger.[17]

Read the full answer ›
Do hyaluronic acid injections help knee osteoarthritis?

Only a little. A 2022 meta-analysis of large placebo-controlled trials found that knee injections lowered pain by 2 mm on a 100 mm scale more than placebo, which is less than patients notice. They also raised the risk of serious adverse events.[3] NICE in the UK advises doctors not to offer them.[19]

Read the full answer ›
Do hyaluronic acid eye drops help dry eyes?

They help about as much as other artificial tears. A 2017 review of 18 studies found that most showed better results with hyaluronic acid drops for damage to the eye surface and for symptoms. When trials were pooled, hyaluronic acid did slightly better on tear production and slightly worse on how long the tear film lasted. The differences were too small to matter in practice.[12]

Open the answer with sources ›
Safety
Who should avoid hyaluronic acid supplements?

EFSA judged rooster comb extract, a source of hyaluronic acid, safe at the use its maker proposed, up to 80 mg a day. The maker's target group was the general population, except three groups: pregnant women, children and people who react to sodium hyaluronate or to bird protein.[1] People in the excluded groups should ask a doctor or pharmacist first.[1]

People who take medicines every day should also ask first, because some dietary supplements interact with prescription or non-prescription medicines.[2]

Open the answer with sources ›
Can you take hyaluronic acid when pregnant or breastfeeding?

There is little data. PubMed searches for this page found no controlled trial of hyaluronic acid supplements in pregnant or breastfeeding women. When EFSA judged rooster comb extract safe, pregnant women were not in the target group that the maker proposed.[1] Ask a doctor or midwife before you take it.[1]

Open the answer with sources ›
Forms and timing
Does the molecular weight of hyaluronic acid matter?

For supplements, it is not clear. In one trial in 61 people with dry skin, hyaluronic acid of 300 kDa and of 800 kDa both raised skin moisture.[13] In creams, only the smaller forms reduced wrinkle depth.[20]

Read the full answer ›
Are hyaluronic acid pills or creams better for skin?

No trial found in PubMed searches for this page compared the two. Both have small trials behind them.[10][20]

  • Pills: a 2025 meta-analysis of 7 trials found better hydration, elasticity and wrinkle depth than with placebo.[10]
  • Creams: in 76 women, creams with 0.1% hyaluronic acid used twice a day for 60 days improved hydration and elasticity around the eyes. Only creams with small molecules (50 and 130 kDa) reduced wrinkle depth.[20]
Open the answer with sources ›

References

  1. Scientific Opinion on Rooster Combs Extract. European Food Safety Authority, 2013. efsa.onlinelibrary.wiley.com
  2. Osteoarthritis: In Depth. National Center for Complementary and Integrative Health, 2016. www.nccih.nih.gov
  3. Viscosupplementation for knee osteoarthritis: systematic review and meta-analysis. Pereira TV, Jüni P, Saadat P, Xing D, Yao L, Bobos P, et al. BMJ, 2022. PMID 36333100
  4. Oral Hyaluronan Relieves Wrinkles and Improves Dry Skin: A 12-Week Double-Blinded, Placebo-Controlled Study. Hsu TF, Su ZR, Hsieh YH, Wang MF, Oe M, Matsuoka R, et al. Nutrients, 2021. PMID 34203487
  5. Ingested hyaluronan moisturizes dry skin. Kawada C, Yoshida T, Yoshida H, Matsuoka R, Sakamoto W, Odanaka W, et al. Nutr J, 2014. PMID 25014997
  6. Oral administration of hyaluronic acid to improve skin conditions via a randomized double-blind clinical test. Gao YR, Wang RP, Zhang L, Fan Y, Luan J, Liu Z, et al. Skin Res Technol, 2023. PMID 38009035

Review history

  1. 9 Nov 2026CheckedReviewerChecked every claim against its source.
  2. 9 Nov 2026Page createdResearcherFirst edition, written from PubMed and public health sources.