Does the size of hyaluronic acid matter?

What was tested

Seventy-six women aged 30–60 used 0.1% HA creams around the eyes for 60 days. Five molecular sizes were tested, from 50 to 2,000 kDa. The other eye received the cream base without HA.

What changed

Hydration and elasticity improved compared with the control. The 50 and 130 kDa groups also showed improvements in measured wrinkle depth after 60 days.

What it means for a serum

Molecular size can matter, but this does not prove that the smallest HA is always best. The study tested specific creams around the eyes, not the five serums here. A label saying “multi-weight” does not reveal the same sizes, concentrations or delivery. None of these brands wins this study.

Formulas to read alongside this paper

• ALASTIN HA IMMERSE Serum
• Dr. Barbara Sturm Hyaluronic Serum
• ISDIN Hyaluronic Concentrate
• PCA SKIN Hyaluronic Acid Boosting Serum
• SkinCeuticals H.A. Intensifier Multi-Glycan

Ingredient overlap is context, not proof of the same concentration, formulation or outcome.