Hyaluronic acid benefits: what the research does and doesn't show

The evidence doesn't support oral hyaluronic acid as a treatment for a joint condition or dry eye disease, and no trial has shown it reverses skin aging. What a handful of small, mostly manufacturer-funded trials found is a modest, measurable improvement in skin hydration, elasticity and wrinkle depth over 8-12 weeks — a narrower claim than the marketing around it.

What the evidence doesn't support

It doesn't support hyaluronic acid, taken by mouth, as a treatment for a diagnosed joint condition, dry eye disease, or any other diagnosed condition. The one placebo-controlled trial we found testing oral hyaluronic acid specifically for knee joint pain found no significant difference between hyaluronic acid and placebo on its main pain measure (PMID 18208600). The one trial testing it for dry eye disease didn't test oral hyaluronic acid alone — every participant, including the control group, used a topical hyaluronic acid eye drop, so the result speaks to combining oral with topical, not to oral hyaluronic acid by itself (PMID 31662894). The skin research is the most developed of the three areas, but even there, a 2025 meta-analysis found some measures — skin firmness, wrinkle volume, water loss through the skin — didn't reach statistical significance, only hydration, elasticity and wrinkle depth did (PMID 40911749). And most of the individual skin trials behind that meta-analysis were funded, or co-authored by employees of, the company selling the hyaluronic acid ingredient tested.

What the trials found

The clearest results are for skin. A 2025 meta-analysis pooled 7 randomized controlled trials of oral hyaluronic acid and found statistically significant improvements in skin hydration, elasticity and wrinkle depth compared with placebo, while firmness, wrinkle volume and transepidermal water loss showed only a non-significant trend toward improvement. The authors flagged small sample sizes and inconsistency between trials as reasons for caution (PMID 40911749).

Individual trials show a similar pattern. A 2023 trial gave 128 healthy women, split into a younger (18-35) and older (45-65) group, either a placebo or 100 mg or 200 mg a day of a 300 kDa hyaluronic acid for 12 weeks; skin hydration improved within 2-8 weeks in both age groups, skin tone within 4-8 weeks, and epidermal thickness by 12 weeks. That trial was funded by the hyaluronic acid manufacturer and didn't report on adverse events one way or the other (PMID 38009035). A 2021 trial gave 40 adults 120 mg a day of hyaluronic acid for 12 weeks and found significant improvements in wrinkle scores, skin water content, water loss through the skin, and elasticity versus placebo, most clearly by 8 and 12 weeks, with no adverse events attributed to it (PMID 34203487). A 2025 trial gave 60 women 60 mg a day of a hyaluronic acid ingredient combined with other glycosaminoglycans and collagen for 12 weeks and found improved wrinkles, smoothness, hydration and skin brightness, again funded by the manufacturer, with no serious adverse events (PMID 40498387). Across these trials, doses ranged from 60 mg to 200 mg a day, all measured over 8-12 weeks — see how much hyaluronic acid should you take a day? for how that compares with what's sold.

The joint research is thinner and less encouraging. A 2008 pilot trial gave 20 adults over 40 with knee pain either 80 mg a day of a chicken-comb-derived hyaluronic acid extract or placebo for 8 weeks. The primary outcome — a standard pain and function score — showed essentially no difference between groups (6.6 points versus 6.4, p=0.943). Both groups improved from their own baseline, and a couple of secondary quality-of-life measures moved somewhat more in the hyaluronic acid group, but with only 10 people per group, the authors themselves said the pilot only "warrants further study in larger sample sizes" (PMID 18208600). We found no larger or more recent placebo-controlled trial of oral hyaluronic acid for joint pain.

The eye research has the same small-and-early quality. A 2019 pilot trial enrolled 54 people with dry eye disease; everyone, including the comparison group, used a topical hyaluronic acid eye drop, and a 24-person subgroup also took oral hyaluronic acid. That combined group improved more than the topical-only group on a dry-eye symptom questionnaire, tear break-up time, and a corneal surface stain over 1 and 3 months. Because nobody in the trial took oral hyaluronic acid without also using the topical drop, this doesn't tell us what oral hyaluronic acid does on its own (PMID 31662894).

Questions people ask

What does a hyaluronic acid supplement do for skin?

Skin is the most-studied area: several small trials found improved skin hydration, elasticity, wrinkle depth and skin tone over 8-12 weeks at 60-200 mg a day, though most were funded by the company selling the ingredient, and a 2025 meta-analysis found not every skin measure reached significance.

Is a hyaluronic acid supplement good for joints?

The only placebo-controlled trial we found testing this directly — 20 people, 8 weeks, 80 mg a day — found no significant difference from placebo on the main pain measure. That's too little evidence, in either direction, to call it good or not good for joints.

Is a hyaluronic acid supplement good for dry eyes?

One small trial found adding oral hyaluronic acid to a topical eye-drop routine improved dry-eye measures more than the drop alone — but because everyone in that trial used the topical drop too, it doesn't show what the oral supplement does by itself.

Is a hyaluronic acid supplement good for hair?

We found no trial measuring hair-related outcomes from oral hyaluronic acid. There's no research basis for that claim in either direction.

What are hyaluronic acid supplement benefits for women?

None of the trials reviewed here isolated a female-specific outcome beyond the fact that most of the skin trials happened to enroll only women, for study-design reasons unrelated to any sex-specific claim. There's no dedicated women's-health research to report.

Is a hyaluronic acid supplement good for dogs or horses?

This page and its citations cover human research only; none of it was conducted in animals. Ask a veterinarian about hyaluronic acid use in a pet or horse.

What does a hyaluronic acid supplement do for fascia, tendons, or the bladder?

We found no trial testing oral hyaluronic acid for fascia, tendon, or bladder-related outcomes. The joint-pain trial above is the closest connective-tissue research available, and it didn't find a benefit over placebo.

When to talk to a doctor

Persistent joint pain, a diagnosed joint condition, or dry eye symptoms that affect daily life are worth raising with a doctor, especially if they're getting worse or not improving. Oral hyaluronic acid is not a treatment for a diagnosed joint condition, dry eye disease, or any other diagnosed condition, and nothing in the research above supports using it as a substitute for a medical evaluation or a treatment a doctor might recommend. If you're pregnant, nursing, or take a prescription medication, talk to a doctor before adding any supplement, hyaluronic acid included.