Minimally packaged, zero-plastic solid shampoo bars are eco-friendly alternatives to regular shampoos, and they are becoming increasingly popular among consumers for whom going green has become a priority. The range of shampoo bars on the supermarket shelf is growing steadily since many people looking for more sustainable personal care products that offer a lower environmental footprint switch to solids.
And although shampoo bars look like bars of soap, these are different types of products, so in this blog post, we’ll compare shampoo bars vs. soap to help you understand how they differ.
Shampoo Bar vs. Soap: Is There a Difference?
Although shampoo bars and soap bars may look, feel, and smell similar and may have some common ingredients, there are many differences. To start with, bar soap is designed to clean your body, while shampoo bars are specifically formulated to remove oils and product build-up from hair. While both personal care products can remove dirt and other impurities and wash away excess oil, the active ingredients that allow each product to do the same job are different.
And the key difference between shampoo bars vs. soap is the pH of the product.
High-quality shampoo bars are delicate and formulated to minimize eye irritation. The pH of well-formulated shampoo bars is about 6.5, which is very similar to the natural pH of our hair and skin. Their pH-balanced formulas contain EWG green-rated ingredients, so these hair care products are free of SLS, parabens, phthalates, synthetic fragrances, and other harsh chemicals commonly found in commercial liquid shampoos. Such chemicals can damage hair, stripping away its healthy natural oils, and can be harmful to the skin.
Unlike commercial shampoos in bottles, the best shampoo bars are made with natural and organic ingredients and contain milder, plant-derived active ingredients, such as sodium cocoyl isethionate (an extremely gentle cleanser derived from coconuts) and fatty alcohols, such as stearyl, cetearyl, or cetyl alcohol that have hydrating properties and help keep hair from drying out. As a result, well-formulated solid shampoo bars are perfect for cleaning any hair type, making it feel soft and manageable, and they are gentle enough for even the most sensitive scalps.
There are well-formulated shampoo bars for every hair type, including dry, oily, curly, coily, and color-treated. Each specific formulation is made with unique ingredients to treat a specific type of hair properly. They also contain moisturizing ingredients, for example, glycerin and proteins, so they clean, condition, and make hair look and feel great after washing. Additionally, mild, all-natural, sulfate-free shampoo bars are multipurpose, so it’s possible to use them as a body, face wash, and shave soap. Since sulfate-free shampoo bars contain ingredients that are gentle on the skin, they are suitable for the whole body.
And what about soap bars? In its essence, true soaps made by a traditional cold-process method are the alkali salts of fatty acids. They are produced by mixing animal fats or plant-based oils with a strongly alkaline solution, such as lye, and the process is known as saponification. When done properly, soap is fabulous to wash with—it smells great, lathers beautifully, and doesn’t over-dry the skin. It’s easily rinsed from the skin, and the skin’s natural acid mantle quickly recovers.
Soap produced by popular brands simply tends to be too strong for regular use on hair since it has a pH level of 9 or 10. Being alkaline, soap disrupts the pH level of hair and the scalp, which is somewhere between 4.5-5.5, meaning it’s slightly acidic. It is too harsh for hair and strips away its natural protective oils, so the hair feels like straw and looks dull and lifeless. Additionally, shampoo bars are made to be easily rinsed even in hard water, while soap may leave a residue on hair roots and scalp, clogging follicles and amplifying hair damage issues. Repeated use of low quality soap to wash hair can even result in permanent damage over time, making hair more brittle, dry, prone to breakage and split ends, and leaving the scalp dry and itchy.
There’s a big difference in the chemical makeup between shampoo bars and soap bars. True soap is excellent in removing dirt and bacteria from the skin. Shampoo bars are formulated specifically for hair, so they are pH-balanced and come packed with additional hydrating, nourishing ingredients for healthier hair over time. Most of these ultra-concentrated, compact cleansers that can last up to 80 washes are typically made without sulfates and other harsh chemicals, so they are gentler on hair and scalp, leaving them clean and healthy.
And since they are made of biodegradable ingredients, save water, and don’t require plastic packaging, these solid shampoos are an excellent option for people who want to adopt a more sustainable beauty routine and reduce their carbon footprint. Still, some shampoo bars contain SLS that can cause skin irritation and artificial fragrances that trigger allergies, so it’s always important to read the ingredient list carefully. It’s better to choose natural hair care products packed with additional hydrating, nourishing ingredients that help make hair shinier, softer, and healthier over time and purchase them from companies focused on sustainability.