Hyaluronic acid (HA) has become a staple in modern skincare, appearing in serums, moisturisers, toners, lip treatments, and even sunscreens. It is celebrated for its extraordinary ability to attract and retain moisture — one gram of hyaluronic acid can hold up to six litres of water. But despite its popularity, a surprising number of people are using it incorrectly, or have fundamental misunderstandings about what it can and cannot do. Here we address the seven most common myths and give you the science-backed truth.
01Myth 1: Hyaluronic Acid Is an Acid That Exfoliates
Despite its name, hyaluronic acid is not an exfoliating acid. Unlike AHAs (glycolic, lactic) or BHAs (salicylic acid), it has no exfoliating properties whatsoever. It is a humectant — a substance that draws moisture from the environment and from deeper layers of the skin to the surface. The word 'acid' in its name refers to its chemical structure (it is a glycosaminoglycan), not its function on the skin. It is gentle enough for the most sensitive skin types, including rosacea-prone skin.
02Myth 2: More Concentration Means Better Hydration
A serum with 2% hyaluronic acid is not necessarily twice as effective as one with 1%. What matters more is the molecular weight of the HA molecules. Low molecular weight HA penetrates deeper into the skin to hydrate from within. High molecular weight HA sits on the surface, forming a moisture-locking film that immediately plumps fine lines and prevents transepidermal water loss. The most effective HA serums use a blend of multiple molecular weights to hydrate at every level of the skin.
03Myth 3: HA Works Best When Applied to Dry Skin
This is probably the costliest misconception about hyaluronic acid. Because HA is a humectant, it draws moisture toward itself from wherever moisture is available. If applied to dry skin in a low-humidity environment, it can actually pull moisture from the deeper layers of your skin, leaving the surface drier than before. Always apply HA to damp skin — spritz your face with water first, or apply it immediately after your toner — and seal it in with a moisturiser on top to prevent evaporation.
04Myth 4: HA Plumps Fine Lines Permanently
Topically applied hyaluronic acid fills in fine lines and gives a temporary plumping effect by drawing water to the surface. This is not the same as the long-term, structural plumping seen with injectable HA fillers. The effect is real and visible but temporary — it lasts as long as the HA remains hydrated in the skin. For longer-term improvements in skin firmness and elasticity, you need to combine HA with collagen-stimulating ingredients like retinol, peptides, or vitamin C.
05Myth 5: Oily Skin Does Not Need Hyaluronic Acid
Oil and water are completely different things. Oily skin can absolutely be dehydrated — lacking in water content — while simultaneously overproducing sebum. Applying a lightweight HA serum actually helps balance oil production by ensuring the skin is adequately hydrated. When the skin is dehydrated, it compensates by producing more oil, which can worsen breakouts and congestion. For oily skin, choose a water-based, gel-textured HA formula without added emollients or occlusive ingredients.
06Myth 6: You Only Need HA in Your Serum
Hyaluronic acid is most effective when layered at multiple steps of your routine. Start with a hydrating toner containing HA for an initial moisture surge, follow with a dedicated HA serum for deeper hydration, and seal everything in with a moisturiser that also contains HA. This multi-layer approach delivers sustained hydration throughout the day and prevents the transepidermal water loss that leaves skin feeling tight and looking dull.
07Myth 7: HA Can Replace a Moisturiser
Hyaluronic acid draws moisture but it cannot seal it in — that is the job of emollients and occlusives (ingredients like ceramides, shea butter, squalane, and petrolatum). Using a HA serum without following it with a moisturiser means the moisture it draws to the surface will simply evaporate into the air. Think of HA as the water and the moisturiser as the lid on the container. You need both for optimal hydration.
Meera Iyer
Skincare Specialist · Your Derm Chronicles