In short
Yes, especially combined with harsh foam. Skin that spent 10 minutes in water at about 41 degrees lost more than twice as much water. Keep the water lukewarm, keep showers short and choose a gentle cleanser.
What do the studies show?
In a study in Spain with 50 volunteers, hands were held in water at about 41 degrees for 10 minutes. The amount of water evaporating from the skin (TEWL, in scientific terms) rose from 25.75 to 58.58 g/h/m². In other words, it more than doubled. It also rose in cold water at 11 degrees, but only to 34.96.
The measurements were taken straight after the water. Wet skin can push this value up a little. Even so, the gap between hot and cold is large.
The real issue is water and foam together
In a study in Denmark with 20 people, arms were immersed twice a day for two days in either plain water or water containing a harsh foaming agent (SLS). Plain water did not change water loss, whether at 20 or at 40 degrees. The water with the foaming agent, however, clearly increased water loss at 40 degrees.
Another study tested the same foaming agent at 4, 20 and 40 degrees. The warmer the water, the more irritated the skin became. In short, hot water amplifies the effect of the foaming agent.
Why does this happen?
The outermost layer of your skin is a thin protective shield. Its cells and the lipids between them keep water in and irritants out. Hot water softens these lipids, and a harsh foaming agent strips them away more easily. With fewer lipids, water escapes and the skin feels tight.
What can you do?
Keep the water lukewarm. Don't linger in the shower; every wash increases water loss a little, and the effect builds up with repetition. Choose a gentle cleanser that is free from harsh sulphates. If your skin is dry, apply a moisturiser after towelling off.
Sources
- Herrero-Fernandez M et al. (2022). Impact of Water Exposure and Temperature Changes on Skin Barrier Function. Journal of Clinical Medicine 11(2):298. doi:10.3390/jcm11020298
- Ohlenschlaeger J et al. (1996). Temperature dependency of skin susceptibility to water and detergents. Acta Dermato-Venereologica 76(4):274–276. doi:10.2340/0001555576274276
- Berardesca E et al. (1995). Effects of water temperature on surfactant-induced skin irritation. Contact Dermatitis 32(2):83–87. doi:10.1111/j.1600-0536.1995.tb00751.x
- Voegeli D (2008). The Effect of Washing and Drying Practices on Skin Barrier Function. Journal of Wound, Ostomy & Continence Nursing 35(1):84–90. doi:10.1097/01.WON.0000308623.68582.d7
- Proksch E, Brandner JM, Jensen JM (2008). The skin: an indispensable barrier. Experimental Dermatology 17(12):1063–1072. doi:10.1111/j.1600-0625.2008.00786.x
These studies were not carried out with EcoProbiotic products.