Dry skin is a common dermatological condition that often affects the elderly. This condition can be uncomfortable and even painful, leading to reduced quality of life. One contributing factor to dry skin is a decreased concentration of hyaluronic acid (HA) in both the epidermis and dermis. Hyaluronic acid is a naturally occurring substance in the skin that helps to retain moisture.

The Role of Hyaluronic Acid Molecular Weight

The effectiveness of HA-containing moisturizers for treating dry skin can be influenced by the specific molecular weight of the HA used. Low molecular weight HA (LMWHA) is believed to be more effective in replenishing skin hydration than high molecular weight HA (HMWHA). This is because LMWHA can penetrate the stratum corneum, the outermost layer of the skin, more easily.

Clinical Evidence

Despite the theoretical advantages of LMWHA, there has been a lack of clinical research supporting its superiority over HMWHA in treating dry skin in the elderly. To address this gap in knowledge, a double-blind, randomized controlled trial was conducted.

The Study

The study involved 36 residents of a nursing home in Jakarta, Indonesia, aged between 60 and 80 years with a diagnosis of dry skin. Each participant received three different moisturizing lotions: one containing LMWHA, one containing HMWHA, and a vehicle (placebo) lotion. The lotions were applied to three separate sites on the leg, and their effectiveness was evaluated over four weeks.

Measurements and Results

Several measurements were taken at the beginning of the study and at weeks 2 and 4:

• Skin capacitance (SCap): A measure of skin hydration.
• Transepidermal water loss (TEWL): A measure of how much water is lost through the skin.
• Specified symptom sum score (SRRC): A measure of the severity of dry skin symptoms.

The results showed that the area treated with LMWHA had significantly higher SCap values compared to the areas treated with HMWHA or the vehicle. This indicates that LMWHA was more effective in improving skin hydration. However, there were no significant differences in TEWL or SRRC scores between the groups, suggesting that all the moisturizers were equally effective in reducing dryness symptoms.

Safety and Tolerability

Importantly, no side effects were reported in any of the groups, demonstrating the safety and tolerability of these moisturizers for treating dry skin in the elderly.

Conclusion

The study findings provide strong evidence that moisturizers containing LMWHA, like the Day and Night Cream from NeuLuna, are more effective than those containing HMWHA or a vehicle in improving skin hydration in the elderly with dry skin. These moisturizers are also safe and well-tolerated, making them a valuable option for treating this common condition.

Reference

Parikesit, M., Novianto, E., Setyorini, M., Legiawati, L., Yusharyahya, S. N. (2024). Effectiveness of topical hyaluronic acid of different molecular weights in xerosis cutis treatment in elderly: a double-blind, randomized controlled trial. Archives of Dermatological Research, 316(3), 329–336. https://doi.org/10.1007/s00403-024-03003-2