Eli5 How is aloe vera gel different than putting water on skin


Pretty much title. How is aloe vera gel supposed to be moisturizing when it’s basically water? Isn’t it the same as putting water on your skin?

In: 4

Aloe Vera isn’t “basically water”. It’s a gel from an aloe vera plant. Aloe contains active compounds that may reduce pain and inflammation and stimulate skin growth and repair.

As with almost anything in, “mostly” X, is not the same thing as X.

Salt water is pretty much just water, but we cant drink it. Similiarly, the to your question answer lies in what is in aloe that ISNT in water.

Specifically, Humectant compounds are one of the conponents in aloe. Normally if you have anything that is wet, the water will enetually evaporate away. It is almost impossible to avoid this evaporation as the humidity in the air is usually way below 100%.

So when you put water on your skin, some tiny fraction might get absorbed, but most of it is going to evaporate, and even the bit that gets absorbed will eventually evaporate as well.

This brings us back to humectants and why they are cool. Instead of letting water evaporate and leave the area (like normal), humectants actually take water from the air. So instead of quickly drying out, aloe will continue to take more water from the air to keep your skin hydrated and moisturized long after plain water would have evaporated.

Moisturizing isn’t about adding water, but preventing the water that is already there from leaving. That’s why treatments of dry skin increase in effectiveness as they decrease in actual water content ( ointment > cream > lotion) because their goal is to provide a barrier – in their case by using oil. Similarly, aloe contains substances (phytosterols) which create a barrier to decrease the skins own water loss. It has nothing to do with “adding water”.