The pH scale measures the acidity or alkalinity of a water-soluble substance (such as the surface of your skin or water). A higher pH number means more alkaline; the lower the number, the more acidic.
At a happy level, your skin’s pH should rest under 5, around 4.7. This means splashing your face with water that’s more alkaline could be ruining your skin. And this doesn’t even include the type of water that might be in your pipes.
Your water could be hard, meaning it contains more minerals than usual, in particular calcium, magnesium, and iron. It can also be soft, meaning it’s lower in minerals than normal. While these minerals are usually fine for drinking, it can cause breakouts, dryness, and irritation on your skin. It could also make dermatitis, eczema, and psoriasis worse.
To check your water’s pH and see if it’s soft or hard, you can ask your water supplier or buy an at-home pH test or a water hardness test. From there, you can decide to buy a water filter for your showerhead.
But your sink water might be a little harder.
If you suspect your tap water is stressing out your skin, you may want to try a different washing method like bottled water or pasteurized milk.
Milk also contains a few components that are good for your skin: It has saturated fats, which can act as moisturizers, and lactose and proteins which can help your skin retain water.
The 30-second beauty routine
Keep whatever liquid you’re using to wash in the fridge. Distilled, reverse osmosis water has a pH around 5 so it’s closer to your skin’s pH. Some people swear by pasteurized milk, but it does have a higher pH at 6.7, so be sure to tone your skin after.
- Take a cup of distilled water or milk with you into the shower.
- Lather up your cleanser with a little bit of liquid and apply it to your face.
- Rinse off the cleanser with the remaining liquid.
Optional: Soak a cotton pad in any leftover milk and swipe it over your face to remove any remaining traces of cleanser. Then proceed with the rest of your routine.
If you decide to skip the distilled water and milk step, opt for a toner instead. Toners are known to help rebalance your skin’s pH to protect your skin’s moisture barrier.
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Michelle explains the science behind beauty products at Lab Muffin Beauty Science. She has a PhD in synthetic medicinal chemistry. You can follow her for science-based beauty tips on Instagram and Facebook.