Did you know that creams with 0.1% hyaluronic acid improved skin hydration and elasticity in 60 days?
An ingredient that holds on to water
Hyaluronic acid is a molecule found naturally in the skin, and it is famous for its ability to bind large amounts of water. This is why it is one of the most widely used ingredients in cosmetics, with the aim of helping the skin keep its hydration, tone and elasticity.
Not all hyaluronic acid is the same. Its molecules can be longer or shorter, and their length is expressed as molecular weight. An interesting question is whether molecular weight changes the result when the molecule is applied in a cream.
How the study was done
In the study, published in 2011, 76 women aged 30 to 60 with wrinkles around the eyes applied a 0.1% hyaluronic acid cream twice a day for 60 days. There were five creams, each with a different molecular weight from 50 to 2,000 kilodaltons, assigned at random.
Around the other eye, each participant applied a control cream without hyaluronic acid. Skin hydration and elasticity were measured before treatment and after 30 and 60 days. At the same time points, replicas of the skin were taken to measure wrinkle depth.
What was observed
All the hyaluronic acid creams significantly improved skin hydration and elasticity compared with the control cream, whatever their molecular weight.
Wrinkle depth told a different story. After 60 days, a significant reduction was seen only with the smallest molecules, those of 50 and 130 kilodaltons. The authors suggest that low molecular weight molecules may penetrate the skin better.
How to read the result
The study has a good design, comparing the two eyes of the same person and repeating instrumental measurements over time. It suggests that the molecular weight of hyaluronic acid really matters.
There are some limits to keep in mind. Each of the five creams was tested on only part of the 76 participants, the study lasted two months and it looked only at the area around the eyes. The explanation based on penetration is a hypothesis of the authors. If the skin around your eyes is sensitive or reacts to products, talk to a dermatologist before changing your routine.
This article is for information only. It does not replace the advice of a doctor or dermatologist, whom you should consult with any question about your skin.