A good skincare routine goes beyond just choosing a nice scent or texture—it involves science too. Among the key factors that influence the effectiveness and safety of cosmetic products, pH plays a fundamental role.

Let’s explore why this value is essential and how to manage it in beauty formulations.

What Is pH and How Does It Work?

Definition of pH

The pH is a numerical value that indicates how acidic or alkaline a water-based solution is. It ranges from 0 to 14. A value below 7 indicates acidity, a value of 7 is neutral, and a value above 7 is considered alkaline.

How pH Is Classified

- From 0 to 7: Acidic (e.g., skin surface)

- 7: Neutral (e.g., pure water)

- From 7 to 14: Alkaline (e.g., certain cleansers)

Where pH Applies

pH can only be measured in water-based solutions, as these can carry electrical charges. This means that pH can't be determined in oil-based mixtures or butters, which don’t contain the elements needed to conduct a current.

Why pH Matters in Skincare and Haircare

Supports Skin’s Natural Balance

Human skin has a slightly acidic surface, usually around pH 5.5. This thin layer, often referred to as the "acid mantle," helps to keep moisture in and unwanted substances out.

A misaligned pH level may lead to irritation or imbalanced skin behavior, depending on the body area. For instance, the face tends to have a pH around 5.5, while more delicate zones are slightly more acidic.

Ensures Product Compatibility

Different products are designed for specific areas and purposes. For example, conditioners often have a pH near 5 to help smooth the hair cuticle and neutralize negative charges, which can otherwise lead to dryness or frizz.

Protects Skin Microbiota

Many skin creams are emulsions—a mix of water and oils. These formulas must be carefully balanced in pH to avoid disturbing the natural microorganisms on the skin. Incorrect values can impact moisture levels, sebum production, and the skin’s overall health.

Stabilizes Active Ingredients

Many protective elements added to cosmetic formulations, such as preservatives, function best within specific pH ranges—commonly below 6. If the pH is outside this range, these ingredients may become ineffective, reducing the product’s shelf life or safety.

How to Measure pH in Your Products

Using pH Meters

For precise results, a digital pH meter is the most effective tool. It's used widely in laboratories and by professional formulators.

Using Litmus Papers

For home use, litmus papers are a practical solution. These papers are treated with a special dye that changes color depending on the solution’s pH.

- Acidic: red to orange

- Neutral: green

- Alkaline: blue to violet

To use, place a small drop of the product on the paper and compare its color to the guide on the packaging.

How to Adjust pH in Homemade Products

Lowering the pH

If the pH is too high, natural acids like citric or lactic acid can be added. These are available in powdered or liquid form and are easy to dose.

Raising the pH

If the pH is too low, it can be increased using a dilute alkaline solution, such as a sodium-based liquid prepared with care. A 30% concentration is commonly used for accuracy.

Application Method

Always add pH adjusters drop by drop, mixing well and checking frequently with a fresh paper. Since a small amount can cause significant changes, it’s better to take the process slowly.

Dosage Tips

The further away the formula is from the desired pH, the more product will be needed to adjust it. Progress gradually and recheck the pH after each step to avoid overshooting the target.

From formulation to final testing, proper pH management is key to safe and successful skincare. Experts like Dr. Zoe Draelos, a dermatologist and researcher, emphasize that "pH plays a vital role in skin compatibility and can influence both the health and appearance of the skin."

In Conclusion

For Lykkers exploring the world of skincare and DIY beauty, understanding pH is a game-changer. It ensures that products work effectively while keeping the skin comfortable and supported. With the right tools and knowledge, anyone can achieve the perfect balance for their beauty creations.