Soap and Skincare: Why It May Not Be the Best Choice for Sensitive, Dry, or Eczema-Prone Skin
By:
Bryan Choong
On
31/10/2024Reading time:
5 min
Summary:
Soap is one of the most common and traditional cleansing agents, used for centuries to keep skin clean and fresh. While it’s effective at removing dirt and oil, soap can be too harsh for people with sensitive, dry, or eczema-prone skin. The ingredients found in many soaps, combined with their drying effects, often cause irritation and compromise the skin’s natural barrier.
In this blog, we’ll discuss why soap can be problematic for sensitive and dry skin, what common ingredients to look out for, and the differences between bar soap and liquid soap.

What Is Soap?
At its core, soap is a cleansing agent made by mixing fats or oils with an alkaline substance like lye (sodium hydroxide for bar soap, potassium hydroxide for liquid soap). This process, known as saponification, produces soap molecules that effectively break down oils and dirt, allowing them to be rinsed away with water.
Soap is available in both bar and liquid forms, and while the base ingredients are similar, there can be variations in the additives, fragrances, and preservatives used.
Why Soap May Not Be Suitable for Sensitive, Dry, or Eczema-Prone Skin
While soap is effective at cleansing, it can be too harsh for people with delicate skin conditions. Here’s why soap may not be the best option for those with sensitive, dry, or eczema-prone skin:
1. Alkaline pH Levels:
Healthy skin typically has a slightly acidic pH of around 5.5, which helps maintain the skin barrier and prevent irritation. Most traditional soaps, however, have an alkaline pH (ranging from 9-10), which can disrupt the skin’s acid mantle. This can weaken the skin’s natural defense, making it more prone to irritation, dryness, and inflammation—especially for those with sensitive or eczema-prone skin.
2. Drying Effects:
Soap is designed to break down oils, but it can strip away not just dirt and excess oils but also the skin’s natural oils that help retain moisture. This can lead to excessive dryness, leaving the skin feeling tight, flaky, and uncomfortable. For people with dry skin or eczema, this stripping effect can exacerbate the condition, leading to further irritation and flare-ups.
3. Harsh Ingredients:
Many commercial soaps contain harsh ingredients such as fragrances, synthetic dyes, and preservatives that can irritate sensitive or compromised skin. These additives can cause allergic reactions, redness, and itching, particularly for people with conditions like eczema or rosacea.
4. Bar vs. Liquid Soap:
While both bar and liquid soaps can contain harsh ingredients, there are some differences between the two. Bar soaps are often made with fewer preservatives but can still have high pH levels and contain drying ingredients. Liquid soaps, on the other hand, tend to have more additives, including fragrances and preservatives, which can irritate sensitive skin. However, many liquid soaps are formulated with gentler surfactants and moisturizing ingredients, making them a better option for sensitive skin than traditional bar soap.
Understanding Soap Ingredients
Soap is made from a combination of fats or oils and lye. Here’s a breakdown of some of the key ingredients used in soap-making and how they may affect your skin:
1. Lye (Sodium Hydroxide or Potassium Hydroxide):
Lye is an essential ingredient in the soap-making process. It’s a strong alkaline substance that reacts with fats or oils during saponification to create soap. While lye is necessary to form soap, the residual alkaline pH it leaves behind can be too harsh for sensitive skin, contributing to dryness and irritation.
2. Palmitic Acid:
Palmitic acid is a fatty acid derived from palm oil, and it’s commonly used in soap-making because it helps create a hard, stable bar of soap. While it contributes to the soap’s durability, it doesn’t offer significant moisturizing benefits, which can be a drawback for people with dry or eczema-prone skin.
3. Lauric Acid:
Lauric acid is found in coconut oil and is prized for its ability to produce a rich lather and enhance the soap’s cleansing properties. However, lauric acid can be too harsh for sensitive skin, as it can strip away natural oils, leading to increased dryness and irritation. While it’s effective at cleaning, its strong cleansing properties can leave sensitive or dry skin feeling tight and uncomfortable.
4. Stearic Acid:
Stearic acid is another fatty acid commonly found in soap. It helps give soap its solid form and provides a creamy lather. However, like palmitic acid, stearic acid doesn’t add moisture to the skin and can contribute to the drying effects of soap.
Bar vs. Liquid Soap
Both bar and liquid soaps can contain similar ingredients, but there are some differences. Bar soaps are often made with fewer preservatives but tend to have a higher pH level, which can be more drying for sensitive skin. Liquid soaps may contain more additives like fragrances and preservatives to maintain shelf life, which can be irritating to sensitive skin. However, some liquid soaps are formulated with gentler ingredients and lower pH levels, making them a better option for delicate skin types.
Alternatives to Traditional Soap
If soap isn’t suitable for your skin, there are plenty of gentler alternatives that provide effective cleansing without causing irritation:
Syndet Bars: Short for “synthetic detergent bars,” syndet bars are soap-free cleansers with a lower pH and are gentler on sensitive or dry skin. These bars are often formulated with mild surfactants and moisturizing ingredients.
Soap-Free Cleansers: Look for soap-free liquid cleansers formulated with mild surfactants like cocamidopropyl betaine or decyl glucoside. These ingredients cleanse the skin without stripping it of its natural oils and are more suitable for those with sensitive or eczema-prone skin.
Moisturizing Body Washes: Many body washes are formulated to cleanse the skin while providing added hydration. Look for products labeled fragrance-free, hypoallergenic, and dermatologist-tested for sensitive skin.
If you struggle with skin sensitivities, consider switching to a soap-free cleanser or a mild syndet bar that won’t disrupt your skin’s moisture barrier or cause irritation. Always choose products formulated for sensitive skin to keep your skin healthy, hydrated, and irritation-free.
While soap can be an effective cleanser for removing dirt and oil, it may not be the best choice for those with sensitive, dry, or eczema-prone skin. The alkaline pH, combined with the potential for irritation from harsh ingredients like sulfates and fragrances, makes traditional soap too drying for these skin types.