A 70 kg adult carries approximately 15 g of hyaluronic acid, of which 5 g are broken down each day, and the skin concentrates about half of it. Over the years, its concentration in the skin decreases: in a study conducted on women's skin, it dropped from 0.030% of skin weight between ages 19 and 47 to 0.007% at age 75. Hence the idea of ingesting it in capsules, powder, or drinkable solution.
This guide focuses on oral intake and brings together what studies identified via PubMed show: the fate of ingested hyaluronic acid, molecular weight, trials on skin, knee and dry eyes, doses and durations tested, the value of collagen and vitamin C, tolerance, the cancer question, and choosing a supplement.
Efficacy : when ingested, hyaluronic acid is mainly broken down by intestinal bacteria; in mice, approximately 0.2% enters the bloodstream. Randomized trials, often small and conducted by manufacturers, nonetheless show a measurable effect on skin hydration and, more modestly, on wrinkles, with 60 to 200 mg per day for 4 to 12 weeks. On arthritic knee, results are more mixed.
Safety : tolerance is good in trials, up to 200 mg per day for 12 months, with rare digestive disorders. No trial has evaluated hyaluronic acid alone during pregnancy, breastfeeding, or childhood. Concerns about cancer are based on laboratory work, not on observations in people who ingest it.
- Hyaluronic acid, what are we talking about?
- When ingested, is it absorbed?
- Low or high molecular weight
- Skin: what randomized trials show
- Joints: trials on the knee
- Dry eyes and other studied uses
- What dose and for how long?
- With collagen and vitamin C
- When and how to take it
- Dangers, side effects, and contraindications
- How to choose a supplement
- Frequently asked questions
Hyaluronic acid, what are we talking about?
Hyaluronic acid is a complex sugar from the glycosaminoglycan family: a long chain that repeats the same pattern of two sugars thousands of times. It is abundant in joint fluid and in the skin, which contains approximately half of the total amount in the body, and retains a large volume of water.
It is a molecule in constant movement: of the 15 g in a 70 kg individual, 5 g are broken down each day. For reference, 200 mg ingested corresponds to 4% of this amount, before their degradation in the intestine: in mice, approximately 0.2% of ingested hyaluronic acid enters the bloodstream. With age, the skin contains less of it: 0.015% of its weight at 60 years old, between the 0.030% and 0.007% mentioned in the introduction. Collagen in the skin also decreases with age, as detailed in our article on collagen loss with age.
Long extracted from rooster combs, hyaluronic acid in supplements is now mainly produced by bacterial fermentation. The molecule is the same; only the possible residues of the process change, a point that matters in case of allergy.
Sodium hyaluronate is the salt form of hyaluronic acid: we are talking about the same molecule. What really distinguishes two ingredients is their molecular weight, that is to say the average length of the chain, expressed in kilodaltons (kDa) or megadaltons (MDa).
When ingested, is it absorbed?
The first animal studies, with a radioactive tracer, diverge. In 2008, in rats, 86.7 to 95.6% of the radioactivity of hyaluronic acid labeled with technetium was excreted, almost entirely in the feces, but some reached the joints, vertebrae, and skin. Another team, using the same tracer in rats, found no significant absorption, only traces with carbon 14. A third, using carbon 14, concluded approximately 90% absorption, with more radioactivity in the skin than in the blood at 24 and 96 hours, but more than 90% was excreted in exhaled air and urine: the molecule had been broken down, then used as an energy source or tissue material. However, a tracer follows the labeled atom, which may have left the molecule.
Subsequent work clarified the mechanism. In rats, hyaluronic acid resists reconstituted gastric and intestinal juices in the laboratory, but it is broken down by the contents of the cecum, at the beginning of the large intestine; the small fragments obtained cross the intestinal wall and were found in the skin. On cultured human intestinal cells, it passes more readily when the molecule is smaller.
With hyaluronic acid labeled with carbon 13, researchers compared normal mice and mice without intestinal bacteria. Bacteria of the Bacteroides genus were essential for absorption: they cut the molecule into small fragments, partially absorbed, the rest becoming short-chain fatty acids. Bioavailability reached only about 0.2%, and the authors conclude an action rather indirect, through general regulation of the organism, than direct on the skin or joints.
Šimek M, Turková K, Schwarzer M, et al. Carbohydr Polym 2023;313:120880. DOI: 10.1016/j.carbpol.2023.120880
Another avenue involves the intestine itself: in mice, a 900 kDa hyaluronic acid given orally binds to an immunity receptor, TLR4, on large intestine cells, and increases the production of an anti-inflammatory molecule, interleukin 10. The large molecule would then not need to be absorbed to act at a distance.
No study directly measures in humans what happens in the skin after a capsule, and much of this work comes from two hyaluronic acid manufacturers, one Japanese, the other Czech. Clinical trials, which measure a result on the skin or knee, therefore count for more.
To act directly on the skin, the topical route remains the other option: our hyaluronic acid serum combines sodium hyaluronate, aloe vera, and glycerin, to apply morning and evening on clean skin, before cream. Our comparison serum or capsules puts the two routes side by side; the rest of this guide remains devoted to the oral route.
Low or high molecular weight
"Low molecular weight" hyaluronic acid is often presented as better absorbed. The argument comes from cultured intestinal cells. But the large molecule is broken down in the intestine anyway, and human trials that compared two sizes did not show a clear advantage.
In 61 Japanese women aged 35 to 60 with dry skin, 120 mg per day of hyaluronic acid at 800 or 300 kDa for 6 weeks increased hydration compared to baseline in both groups, remaining stable under placebo; the difference from placebo only became significant for 300 kDa, two weeks after stopping. In 60 Japanese adults with crow's feet wrinkles, 120 mg per day of 2 or 300 kDa for 12 weeks reduced wrinkle volume compared to placebo at 8 weeks with 300 kDa, with a trend for 2 kDa (p = 0.052); perceived radiance and firmness improved in all groups, including placebo.
Results were obtained with sizes ranging from 300 kDa to 1.8 MDa, a trend with 2 kDa, or with size mixtures (table in the next section). The molecular weight listed on a label helps compare a product to studies, but no size has shown clear superiority in humans: daily dose and duration of use carry more weight.
Skin: what randomized trials show
Skin is the best-studied area. In Taiwan, in 40 adults aged 35 to 64, 120 mg per day for 12 weeks produced higher facial hydration than placebo (p = 0.02), lower water loss through the skin, and better elasticity, with differences appearing only after 8 weeks. The trial remains small, and the hyaluronic acid tested came from a Japanese manufacturer heavily involved in this research.
In 150 adults aged 18 to 60, a drinkable solution of microbial-origin sodium hyaluronate (1.8 MDa), taken each morning at 60 or 120 mg, was compared to placebo for 3 months in autumn and winter. Cheek hydration increased by 9.1% (60 mg) and 11.5% (120 mg) more than placebo, water loss through the skin decreased, and wrinkle depth around the eyes was reduced from the first month. Adverse effects, mild, were equally frequent under placebo.
Dolečková I, Kušnierik P, Berka V, et al. Sci Rep 2026;16(1):2941. DOI: 10.1038/s41598-025-32758-5
This trial, conducted by the ingredient manufacturer, is the largest of the trials presented here and one of the few in people with light skin. Nothing changed for redness, pores, or skin color, and the authors note a short duration, possible seasonal influence, and they did not correct statistics for the large number of measurements.
In Italy, in 60 women, 200 mg per day of fermented hyaluronic acid, a mixture of multiple sizes, was compared to placebo for 28 days: in the supplemented group, hydration increased by 10.6% and wrinkle depth decreased by 18.8% compared to baseline, with the abstract not quantifying the difference from placebo. In Spain, a matrix combining hyaluronic acid, other glycosaminoglycans, and collagen improved wrinkles, smoothness, and skin roughness compared to placebo; this is a mixture.
| Trial | Population | Dose and duration | Result |
|---|---|---|---|
| Kawada, 2015 | 61 Japanese women with dry skin | 120 mg per day (800 or 300 kDa), 6 weeks | Higher hydration than placebo 2 weeks after stopping (300 kDa) |
| Oe, 2017 | 60 adults with crow's feet wrinkles | 120 mg per day (2 or 300 kDa), 12 weeks | Lower wrinkle volume than placebo at 8 weeks (300 kDa) |
| Hsu, 2021 | 40 adults aged 35 to 64 | 120 mg per day, 12 weeks | Better hydration, barrier, and elasticity than placebo |
| Michelotti, 2021 | 60 women | 200 mg per day (size mixture), 28 days | Improved hydration, wrinkles, and elasticity in the active group |
| Montero-Vilchez, 2025 | 60 women aged 35 to 65 | 60 mg per day of a matrix with collagen, 12 weeks | Improved wrinkles, smoothness, and roughness compared to placebo |
| Dolečková, 2026 | 150 adults aged 18 to 60 | 60 or 120 mg per day (1.8 MDa) in solution, 3 months | Hydration +9.1 and +11.5% versus placebo, wrinkles reduced from 1 month |
A 2025 meta-analysis combining 7 randomized trials of oral hyaluronic acid found significant improvement in hydration, elasticity, and wrinkle depth, but not in firmness, wrinkle volume, or transepidermal water loss; its authors consider the sample sizes limited and the trials too heterogeneous to draw firm conclusions. We therefore speak of modest effects, measured by devices, rather than spectacular transformations. For wrinkles, other active ingredients have their own data, presented in our article on collagen and wrinkles.
Joints: knee trials
Hyaluronic acid lubricates synovial fluid, and its injection into the knee is part of medical treatments for osteoarthritis. Its oral intake has therefore been tested, with more mixed results than on skin.
In 60 Japanese aged 50 and over with grade 2 or 3 knee osteoarthritis, 200 mg per day of hyaluronic acid of approximately 900 kDa, taken after breakfast, was compared to placebo for 12 months, with all participants performing daily quadriceps strengthening. Symptoms improved in both groups, with no significant difference in the overall score. In those aged 70 or younger, the score was better with hyaluronic acid at 2 and 4 months.
Tashiro T, Seino S, Sato T, et al. ScientificWorldJournal 2012;2012:167928. DOI: 10.1100/2012/167928
| Trial | Population | Intake and duration | Result |
|---|---|---|---|
| Kalman, 2008 | 20 adults, knee osteoarthritis | 80 mg of rooster comb extract, 8 weeks | No difference in pain versus placebo (p = 0.943) |
| Solà, 2015 | 80 adults, mild knee pain | 80 mg of rooster comb extract in yogurt, 12 weeks | Knee strength +11% at least in men, nothing in women |
| Nelson, 2015 | 40 obese adults, knee osteoarthritis | Preparation with other glycosaminoglycans, 3 months | Pain and function improved, inflammatory markers decreased |
| Hill, 2023 | 100 adults, mild knee or hip osteoarthritis | Krill, astaxanthin and hyaluronic acid, 12 weeks | Pain −20.8 versus −10.6 mm under placebo |
| Sugiyama, 2024 | Adults without confirmed osteoarthritis | 111 mg per day, 12 weeks | Pain, stiffness and discomfort reduced compared to placebo |
A 2024 systematic review gathered 11 publications and 597 patients, almost all with osteoarthritis, taking 30 to 300 mg per day for 4 weeks to 12 months. Nine showed at least one improvement, and adverse effects were rare and mild. But in 9 out of 11 trials, hyaluronic acid was combined with other substances, which prevents attributing the benefit to it alone.
What relieves arthritic knee pain is better established: according to a Cochrane review (44 trials, 3,537 participants for pain, measurements at end of program), therapeutictherapeutic exercise reduces pain by 12 points on a 100-point scale and improves physical function by 10 points. Hyaluronic acid injections into the joint are a distinct medical procedure, to be discussed with your doctor, and no study shows that a supplement replaces them. Our guide onosteoarthritis details the validated approaches, and our article on collagen for joints presents another active ingredient often used in combination.
Dry eyes and other studied uses
Treatment of dry eye typically begins with artificial tears, some of which contain hyaluronic acid. The oral route was tested as a supplement to this eye drop.
In 54 patients with dry eye, all treated with 0.15% hyaluronic acid eye drops, 24 additionally received 240 mg per day of 390 kDa hyaluronic acid orally for 3 months. Eye surface lesions regressed more in this group at 1 and 3 months, and the ocular discomfort score was better at 3 months, with no difference in tear film stability. The trial was neither blinded nor placebo-controlled.
Kim Y, Moon CH, Kim BY, Jang SY. J Ophthalmol 2019;2019:5491626. DOI: 10.1155/2019/5491626
In chronic lower back pain, 60 patients underwent 3 weeks of physical therapy alone or combined with a blend of collagen peptides, vitamin C, sodium hyaluronate, manganese and copper: both groups improved, more so with the blend, though the contribution of hyaluronic acid alone could not be isolated.
What dose and for how long?
No reference dose has been established, but trials outline a clear range. For skin, they used 60 to 200 mg per day, most often 120 mg; for joints, 30 to 300 mg, often in blends; the dry eye trial, 240 mg. In the 150-adult trial, 120 mg showed more marked effects than 60 mg, a trend to be confirmed, and no study has sought the minimum effective dose.
Duration matters just as much: effects on skin appeared between 4 weeks, in the Italian trial and for wrinkles in the 150-adult trial, and 8 weeks in the Taiwanese trial, whose authors note that the epidermis renews in approximately 28 days.
Our Marine Collagen and Hyaluronic Acid in Capsules provides 200 mg of hyaluronic acid per 4 capsules: this is the daily dose from the 28-day Italian trial on skin, conducted with fermentation-derived hyaluronic acid in multiple sizes, and the 12-month Japanese trial on the knee, conducted with hyaluronic acid of approximately 900 kDa, with no significant difference from placebo on overall score but well tolerated. These trials tested hyaluronic acid alone; our formula combines it with marine collagen and vitamin C, and a result does not automatically transfer from one formula to another.
Look at the amount of hyaluronic acid per daily dose, not per capsule: 50 mg per capsule becomes 200 mg if you need to take four. A few milligrams, far from the 60 to 200 mg in trials, serves as a supporting ingredient.
With collagen and vitamin C
Hyaluronic acid and collagen have been studied separately. For hydrolyzed collagen alone, a meta-analysis of 26 randomized trials and 1,721 participants found, compared to placebo, an improvement in skin hydration (effect size 0.63) and elasticity (0.72). By convention, 0.2 corresponds to a small effect, 0.5 to a medium effect and 0.8 to a large effect: results fall between medium and large. Benefits were more pronounced from 8 weeks onward, most often with 2.5 to 10 g per day, a few trials using around 1 g; the authors note several biases.
Vitamin C, present in high concentration in skin, stimulates collagen production and participates in antioxidant protection against ultraviolet rays; however, a 2017 review notes that the benefit of oral supplementation, compared to skin application, remains poorly understood. Our article on natural vitamin C presents the sources. The combinations themselves have been little tested, and no trial has specifically addressed our formulas, which combine active ingredients that have each been studied.
If your priority is to approach the collagen doses from trials, our Marine collagen and hyaluronic acid powder provides 10 g of Naticol® marine collagen per day, at the high end of the usual range, with 210 mg of hyaluronic acid. The capsules provide 1,208 mg of collagen, close to the few trials conducted around 1 g but below the most studied range of 2.5 to 10 g, and 200 mg of hyaluronic acid. Our article on the daily dosage of marine collagen details these benchmarks.
When and how to take it
No study has compared morning versus evening. In three trials, intake took place in the morning or after breakfast; consistency remains most important. Our 4 capsules are taken with a large glass of water, possibly spread throughout the day. Our powder dissolves in water, juice, milk, tea, or coffee; let it hydrate for 10 to 15 seconds before stirring. Our article when to take collagen complements these tips.
A supplement does not compensate for what damages the skin: sun protection, smoking cessation, varied diet, and sufficient sleep remain the primary levers, as our article on antioxidants and oxidative stress.
Dangers, side effects, and contraindications
Tolerance is good in randomized trials: no skin adverse effects in the dry skin trial, no adverse events in the wrinkles trial, mild effects as frequent under placebo in the 150-adult trial. Over 12 months, 4 participants on hyaluronic acid experienced possible digestive disorders (gastric discomfort, reflux, loss of appetite), versus 2 skin irritations under placebo, with no significant difference or established causal link. In an osteoarthritis trial with a mixture containing hyaluronic acid, adverse effects were more frequent under placebo, 16% versus 4%.
In rats, an extract of rooster comb rich in sodium hyaluronate caused no significant adverse effects for 90 days, up to 600 mg per kilogram of body weight per day, and was not mutagenic. An expert report concludes, based on animal and laboratory studies, that hyaluronic acid is neither genotoxic, nor toxic to reproduction or development, nor a sensitizer.
Pregnancy, breastfeeding, children. These animal data do not replace human trials: none has evaluated hyaluronic acid alone in pregnant or breastfeeding women, whom the largest skin trial excluded, nor in children; the rare studies conducted during pregnancy test a nutrient blend, under medical supervision. During pregnancy and breastfeeding, consult a healthcare professional before taking our capsules or powder; our drinkable collagen is, conversely, not recommended in these situations or in children.
Allergies. Hyaluronic acid from rooster comb and that from fermentation do not have the same possible manufacturing residues. If you are allergic to poultry proteins, check the source of the ingredient and ask your allergist's opinion, as a precaution. Since marine collagen is derived from fish, a fish allergy warrants the same approach, as detailed in our article on dangers of marine collagen.
Interactions. The cited trials do not report drug interactions, without being designed to investigate them: if taking long-term treatment, discuss this with your doctor or pharmacist.
And cancer? The question comes from the laboratory. Hyaluronic acid breaks down into fragments whose properties change with size: the large molecule is rather hydrating and anti-inflammatory, whereas fragments of around 20 kDa promote inflammation and blood vessel formation in cells, and cancer cells divert the production and cleavage of their own hyaluronic acid to grow. But these observations concern hyaluronic acid produced in the tumor, not the kind you swallow; some of the effects attributed to small fragments could come from contamination of preparations by bacterial toxins; high molecular weight form is even associated, in certain models, with cancer resistance; and in mice, barely 0.2% of swallowed hyaluronic acid reaches the bloodstream. The 2009 expert report concludes that it probably plays no causal role in metastases. No clinical trial, lasting 12 months at most, has reported problems of this type. In case of current or past cancer, discuss it with your oncologist.
Pregnancy and breastfeeding : no data on hyaluronic acid alone, consult a healthcare professional before any use. Children : no trials. Allergy to poultry or fish proteins : check the origin of ingredients and seek medical advice. Current or past cancer, long-term treatment : discuss with your doctor. Digestive disorders : rare in trials, they justify stopping and consulting if they persist.
How to choose a supplement
The decisive criterion is the amount of hyaluronic acid per daily dose, to be compared with the 60 to 200 mg per day from skin trials. Molecular weight, origin, and form are useful information, without being decisive.
| Criterion | What to look at | Trial reference |
|---|---|---|
| Hyaluronic acid dose | The quantity per day, not per capsule | 60 to 200 mg per day for skin |
| Duration | Number of days covered by a box | 4 to 12 weeks, up to 12 months well tolerated |
| Molecular weight | Indicated or not | From 300 kDa to 1.8 MDa, trend with 2 kDa, without notably larger size |
| Origin | Fermentation or rooster comb | Useful especially in case of poultry protein allergy |
| Associated formula | Collagen dose, vitamin C | Collagen: most often 2.5 to 10 g per day in trials |
An associated formula is read ingredient by ingredient. Our Marine collagen drink, for example, contains 10 mg of hyaluronic acid per shot, well below trial doses: its interest lies mainly in its 5,000 mg of Naticol® marine collagen, with 60 mg of vitamin C and 20 mg of coenzyme Q10, in a 20-day course. It is not recommended for children, pregnant or breastfeeding women, and in case of allergy to salicylate derivatives. For hyaluronic acid, our capsules and our powder, with 200 and 210 mg per day, match the trial doses. Our guide to choosing a collagen Complete this grid.
200 mg of hyaluronic acid and 1,208 mg of hydrolyzed marine collagen Naticol per day, with 160 mg of vitamin C and 3.96 mg of manganese, in vegetable capsules. Four capsules per day with a large glass of water, distributed throughout the day if desired; one pill organizer covers one month and the formula is taken year-round.
View Marine Collagen in capsulesDo you prefer a drink? Our Marine collagen powder provides 10 g of marine collagen and 210 mg of hyaluronic acid per day.
Frequently asked questions
Is hyaluronic acid in capsules effective?
On the skin, yes, modestly: with 60 to 200 mg per day for 4 to 12 weeks, randomized trials show better hydration and slightly less pronounced wrinkles than with placebo. These trials often remain small and conducted by manufacturers. On the knee, results are more mixed.
Is hyaluronic acid in capsules dangerous?
Trials have not revealed any danger in healthy adults, up to 200 mg per day for 12 months, and animal toxicology studies are reassuring. Unknowns concern pregnancy, breastfeeding, and childhood, due to lack of trials on hyaluronic acid alone.
What are the side effects of hyaluronic acid in capsules?
They are rare and mild in trials. In the 12-month trial, a few possible digestive issues were noted, with no significant difference from placebo. In the trial of 150 adults, mild adverse effects were just as common under placebo.
Can hyaluronic acid in capsules cause cancer?
No human study shows this. The concern stems from laboratory work on hyaluronic acid produced by tumors themselves. In mice, barely 0.2% of ingested hyaluronic acid enters the bloodstream, and an expert report concludes it likely plays no causal role in metastases. In case of current or past cancer, ask your oncologist for advice.
What dose of hyaluronic acid should I take per day?
Skin trials used 60 to 200 mg per day, most often 120 mg. On joints, studied doses range from 30 to 300 mg per day, often in blends. Read the quantity per daily dose and not per capsule.
How long should I take hyaluronic acid in capsules?
At least 8 to 12 weeks before judging: the first differences from placebo appeared between 4 and 8 weeks depending on the trials. The longest studied intake, 12 months at 200 mg per day, was well tolerated.
When should I take hyaluronic acid, morning or evening?
No study has compared the two. In several trials, intake was in the morning or after breakfast. Most importantly, take it every day at the same time.
Low or high molecular weight hyaluronic acid: which to choose?
Small molecules cross intestinal cells better in culture, but in humans, forms ranging from 300 kDa to 1.8 MDa showed results, and 2 kDa a trend, with no clear advantage of one size over another. Dose and duration matter more.
Are collagen and hyaluronic acid capsules dangerous?
Both ingredients are well tolerated in trials in adults. Precautions concern pregnancy and breastfeeding, where medical advice is necessary, and allergies to fish or poultry proteins.
Can I take hyaluronic acid while pregnant or breastfeeding?
No trial has evaluated hyaluronic acid alone during pregnancy or breastfeeding, and the largest skin trial excluded these situations. Consult your doctor or midwife before starting any intake.
Does hyaluronic acid in capsules work on joints?
Results are mixed. In a 12-month trial at 200 mg per day, combined with muscle strengthening, the benefit appeared only in those 70 years or younger, at 2 and 4 months, and most other trials tested blends. Therapeutic exercise remains the standard treatment for knee osteoarthritis.
Do hyaluronic acid capsules replace injections?
No. Injections, to the face or knee, are medical procedures with their own indications, and no study shows that a supplement replaces them or extends their effect. Capsules aim for modest action on skin hydration.
Sources
The studies cited below were identified via PubMed.
- Stern R. The catabolism of hyaluronic acid: a new metabolic pathway. European Journal of Cell Biology, 2004;83(7):317-325. DOI
- Kawada C, Yoshida T, Yoshida H, et al. Ingested hyaluronic acid hydrates dry skin. Nutrition Journal, 2014;13:70. DOI
- Longas MO, Russell CS, He XY. Indices of structural modifications of dermatan sulfate and hyaluronic acid with age. Carbohydrate Research, 1987;159(1):127-136. DOI
- de Oliveira JD, Carvalho LS, Gomes AM, et al. Genetic basis of hyaluronic acid overproduction in natural and modified microorganisms. Microbial Cell Factories, 2016;15(1):119. DOI
- Becker LC, Bergfeld WF, Belsito DV, et al. Final report on the safety assessment of hyaluronic acid, potassium hyaluronate and sodium hyaluronate. International Journal of Toxicology, 2009;28(4 Suppl):5-67. DOI
- Balogh L, Polyak A, Mathe D, et al. Absorption, uptake and tissue affinity of high molecular weight hyaluronic acid after oral administration in rats and dogs. Journal of Agricultural and Food Chemistry, 2008;56(22):10582-10593. DOI
- Laznicek M, Laznickova A, Cozikova D, Velebny V. Preclinical pharmacokinetics of radiolabeled hyaluronic acid. Pharmacological Reports, 2012;64(2):428-437. DOI
- Oe M, Mitsugi K, Odanaka W, et al. Dietary hyaluronic acid migrates into rat skin. The Scientific World Journal, 2014;2014:378024. DOI
- Kimura M, Maeshima T, Kubota T, et al. Absorption of orally administered hyaluronic acid. Journal of Medicinal Food, 2016;19(12):1172-1179. DOI
- Hisada N, Satsu H, Mori A, et al. Low molecular weight hyaluronic acid crosses human intestinal epithelial Caco-2 cell monolayers via the paracellular pathway. Bioscience, Biotechnology, and Biochemistry, 2008;72(4):1111-1114. DOI
- Šimek M, Turková K, Schwarzer M, et al. Molecular weight and gut microbiota determine the bioavailability of orally administered hyaluronic acid. Carbohydrate Polymers, 2023;313:120880. DOI
- Asari A, Kanemitsu T, Kurihara H. High molecular weight hyaluronic acid (900 kDa) administered orally regulates the immune system via the TLR4 receptor of intestinal epithelium. The Journal of Biological Chemistry, 2010;285(32):24751-24758. DOI
- Kawada C, Yoshida T, Yoshida H, et al. Ingestion of hyaluronic acid (molecular weights of 800 k and 300 k) improves dry skin: a randomized, double-blind, placebo-controlled trial. Journal of Clinical Biochemistry and Nutrition, 2015;56(1):66-73. DOI
- Oe M, Sakai S, Yoshida H, et al. Oral hyaluronic acid attenuates wrinkles: a 12-week double-blind, placebo-controlled trial. Clinical, Cosmetic and Investigational Dermatology, 2017;10:267-273. DOI
- Hsu TF, Su ZR, Hsieh YH, et al. Oral hyaluronic acid attenuates wrinkles and improves dry skin: a 12-week double-blind, placebo-controlled trial. Nutrients, 2021;13(7):2220. DOI
- Dolečková I, Kušnierik P, Berka V, et al. Oral sodium hyaluronate improves hydration, barrier function, and signs of skin aging: a randomized, double-blind, placebo-controlled trial in 150 healthy adults. Scientific Reports, 2026;16(1):2941. DOI
- Michelotti A, Cestone E, De Ponti I, et al. Oral intake of a novel full-spectrum hyaluronic acid improves skin profilometry and aging: a randomized, double-blind, placebo-controlled clinical trial. European Journal of Dermatology, 2021;31(6):798-805. DOI
- Montero-Vilchez T, Gálvez-Martín P, Sanabria-de la Torre R, et al. Oral supplementation with a novel hyaluronic acid matrix ingredient improves skin radiance, hydration, smoothness, and roughness: a randomized, double-blind, placebo-controlled trial. Dermatology and Therapy, 2025;15(8):2099-2116. DOI
- Amin P, Sarabi A, Choe S, et al. Oral hyaluronic acid supplement: efficacy on hydration, elasticity, and wrinkle depth. Journal of Drugs in Dermatology, 2025;24(9):910-919. DOI
- Tashiro T, Seino S, Sato T, et al. Oral administration of polymer hyaluronic acid attenuates symptoms of knee osteoarthritis: a 12-month double-blind, placebo-controlled trial. The Scientific World Journal, 2012;2012:167928. DOI
- Kalman DS, Heimer M, Valdeon A, et al. Effect of a natural rooster comb extract rich in hyaluronic acid on pain and quality of life in knee osteoarthritis: a randomized, double-blind, placebo-controlled pilot trial. Nutrition Journal, 2008;7:3. DOI
- Solà R, Valls RM, Martorell I, et al. A reduced-fat yogurt enriched with rooster comb extract and muscle and joint function in adults suffering from mild knee pain: a randomized double-blind placebo-controlled trial. Food & Function, 2015;6(11):3531-3539. DOI
- Nelson FR, Zvirbulis RA, Zonca B, et al. Effects of an oral preparation containing hyaluronic acid in obese patients with knee osteoarthritis: pain, function, bradykinin, leptin, inflammatory cytokines and heavy water analyses. Rheumatology International, 2015;35(1):43-52. DOI
- Hill WS, Dohnalek MH, Ha Y, et al. A multicenter randomized double-blind placebo-controlled trial evaluating the efficacy and safety of an oral complex of krill oil, astaxanthin and hyaluronic acid on joint health in mild osteoarthritis. Nutrients, 2023;15(17):3769. DOI
- Sugiyama K, Oe M, Tanaka T, et al. Oral sodium hyaluronate relieves knee discomfort: a 12-week double-blind placebo-controlled trial. Experimental and Therapeutic Medicine, 2024;27(2):64. DOI
- de Carvalho JF, Davidson J. Oral hyaluronic acid in osteoarthritis and low back pain: a systematic review. Mediterranean Journal of Rheumatology, 2024;35(4):557-562. DOI
- Fransen M, McConnell S, Harmer AR, et al. Exercise for knee osteoarthritis. The Cochrane Database of Systematic Reviews, 2015;1:CD004376. DOI
- Kim Y, Moon CH, Kim BY, Jang SY. Oral hyaluronic acid supplementation in the treatment of dry eye: a pilot study. Journal of Ophthalmology, 2019;2019:5491626. DOI
- Farì G, Santagati D, Pignatelli G, et al. Collagen peptides associated with vitamin C, sodium hyaluronate, manganese and copper in the rehabilitation of chronic low back pain. Endocrine, Metabolic & Immune Disorders Drug Targets, 2022;22(1):108-115. DOI
- Pu SY, Huang YL, Pu CM, et al. Effects of oral collagen on skin aging: a systematic review and meta-analysis. Nutrients, 2023;15(9):2080. DOI
- Pullar JM, Carr AC, Vissers MCM. The roles of vitamin C in skin health. Nutrients, 2017;9(8):866. DOI
- Canut L, Zapatero J, López S, et al. Genotoxicity, acute and subchronic toxicity in rats of a rooster comb extract rich in sodium hyaluronate. Regulatory Toxicology and Pharmacology, 2012;62(3):532-541. DOI
- Porcaro G, Laganà AS, Neri I, Aragona C. The combination of high molecular weight hyaluronic acid, alpha-lipoic acid, magnesium, and vitamins B6 and D improves resorption of subchorionic hematoma in threatened miscarriage: a pilot clinical study. Journal of Clinical Medicine, 2024;13(3):706. DOI
- Liu M, Tolg C, Turley E. Understanding the dual nature of hyaluronic acid in the tumor microenvironment. Frontiers in Immunology, 2019;10:947. DOI
- Weigel PH. Designing, evaluating, and controlling signaling studies to assess size-dependency and specificity of hyaluronic acid. Glycobiology, 2017;27(9):796-799. DOI
