The Science Behind: Hyaluronic Acid

New series alert: informed choices is certainly not done and I want to keep chipping away at it in the new year, but I also want to bring a more widely applicable series to the blog. “The Science Behind” is going to be an evidence review of common products, medications, vitamins, supplements and more so that you can gain a better understanding of 1) what different things are; and 2) what they are proven to work for. As a previous student of history, I will also do my best (where information is available) to look at any historical and/or cultural uses/applications of different things.

This is generally what I do on my blog – evidence reviews! But, I want to focus on “hot topic” ingredients and products I see advertised a lot so we can all gain a better understanding of what we might use or consider using. It is essentially another version of informed choices – but not just for pregnancy and birth.

Disclaimer: this is not medical advice. This blog is for informational purposes only. Please seek medical advice from your trusted, regulated healthcare professional.

What is hyaluronic acid?

Hyaluronic acid is a substance that retains moisture (a.k.a. a humectant). We actually already have it in and on our bodies – including on our skin and it is a part of synovial fluid (around your joints). But as we get older, hyaluronic acid decreases in these areas – which is why older people may experience dry skin and other related symptoms.

The hyaluronic acid that is in your skincare products is made in a lab through biofermentation. This actually enhances its ability to be absorbed by the skin. This is not a scientific link but it actually is a very good/interesting article and slideshow on biofermentation.

What are the claims – what is it supposed to do?

Hyaluronic acid generally claims to hydrate the skin. Drs. Liu and Nassim say this does happen – but it depends on the size of the molecule, as they vary. With larger molecules, hydration only happens at a surface level with skincare products, whereas smaller molecules are able to penetrate deeper though still only into the top layer of skin, the epidermis (excuse my vary basic image!). A small study done in 2014 showed that Nano-HA was beneficial for wrinkles, hydration and even skin firmness within 2 months. A more recent but still smaller study done in 2021 similarly showed benefits from topical HA for skin hydration.

Drs. Liu and Nassim recommend looking for products that contain a variety of molecular sizes for maximal hydration.

Does it work?

So the conclusion is – yes, hyaluronic acid is an effective moisturizer for your skin on the surface and/or outermost layer, depending on the variety in molecular size. Smaller sizes may have the potential (based on some research) to provide increased benefits to the skin.

It does not work as well in a skincare product for changes in skin volume and/or laxity, as it would in a hyaluronic acid dermal filler though. This requires access to deeper layers of the skin.

It is safe?

Yes! Generally, HA is safe and tolerated by most peopleyou should always consult your doctor if you have questions or concerns though about its use. It is not related to many allergic reactions, and bonus: it’s safe in both pregnancy and breastfeeding.

Additional Resources

“The hype on hyaluronic acid” by Drs. Liu and Nassim (Dermatology)


2 responses to “The Science Behind: Hyaluronic Acid”

  1. Great educational post! My skin has become a lot better since I started adding a pure hyaluronic acid to my routine!

    Looking forward to your next post!

    Rose | Beauty & Lifestyle Blogger
    @rosemaryhelenxo |


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