Liquid soap vs. Solid soap: What is the better choice?

On average, we wash our hands between 10 to 15 times per day. If possible, this should be done thoroughly and with warm water after each visit to the toilet, before preparing meals, after coming home, and after each contact with potential germ carriers – this has become even more important in our current situation. Indeed, hygiene has become more important than ever before. Nevertheless, the question of which soap is most effective for washing hands often remains unanswered. In the following article, we will compare liquid and solid soap and explain their respective advantages and disadvantages.

Händewaschen, Seife, Schaum, Wasser, Wasserhahn

Although the traditional solid soap bar has recently returned to many bathrooms, opinions about solid soap are often divided. Unhygienic, impractical and dehydrating are often keywords that come up in the conversation in regard to solid soap. At the same time, liquid soap is also being criticized for being unsustainable in terms of production and packaging. The latter being deemed as disdainful by some environmentalists. On closer inspection of both soap forms, however, the advantages of each product cannot be denied.

Solid Soap

Soap is made when fats are broken down by the process known as „saponification“. Depending on the chain length of the fatty acids released by the cooking process, the soap will have a softer or harder consistency. This, in turn, will result in softer soap or harder soap. In most cases, vegetable or animal fats, such as olive, palm, or coconut fat, are used to produce solid soaps. With less high-quality soaps, however, oftentimes animal sodium fat or leftover fat from slaughterhouses are also contained, which is supposed to be covered by strong smelling perfumes.

Lavendelseife, Handtuch, Lavendel

Advantages

Solid soap bars have a fairly basic (alkaline) pH value. This often leads to the assumption that solid soaps attack or damage the skin. Yet, oftentimes it is overlooked that the water used for washing neutralizes this soap’s alkaline pH value quite quickly. Therefore, the solid soap is, contrary to its reputation, not harmful to the skin. Another advantage of solid soap is its refatting and mild effect which actually results in the skin drying out less. In addition, a solid bar of soap causes the skin to soften slightly, thus improving water absorption and water storage. Natural additives, such as lavender, sage, or rose, are also a reason for many people to use solid soaps instead of their liquid counterparts.

In addition to the solid soap’s grooming advantages, for many people one factor is particularly decisive when deciding to purchase a solid soap: solid soaps are more sustainable and better for the environment than liquid soaps. This is mostly due to solid soaps being produced without chemical additives. Hence, solid soaps can be broken down more gently in the long term. Furthermore, a solid soap bar lasts for several months, even when used daily. Moreover is it available at a lower price as compared to liquid soaps. Concurrently, the solid soap bar is usually not wrapped in plastic packaging, which benefits the environment as well.

Disadvantages

Despite many positive aspects of the solid soap bar, there are also many voices supporting the ban of conventional soap from German bathrooms since the 1980s. Because for many people the solid soap bar is a real bacterial focus, especially if it is shared by several people. With a shared solid soap bar it is uncertain what the previous person had on his hands. Many people fear that this dirt is now possibly stuck to the soap bar. This is exactly the reason why soap dispensers with liquid soap are now common in all public washrooms.

However, experts have found that bacteria and germs have no chance of survival on the alkaline surface of soap. Ironically, bacteria and germs survive more easily on pump dispensers for liquid soap. In terms of the solid soap bar, what you should pay attention to is the regular cleaning of the soap dish where you keep your soap bar. Bacteria and germs can feel very comfortable on it.

Liquid soap

Despite its misleading name, liquid soap is not soap in its true and classical sense. The liquid is rather a solution or emulsion of syndets (abbreviated to „synthetic detergents“), i.e. substances that facilitate cleaning, mixed with water. Appreciated by many for its practicability, liquid soap is based on an acidic or synthetic foundation. These foundations are adjusted to the skin’s pH value. Our skin’s pH value is between 4.1 and 5.8. As a result, liquid soaps appear to be more skin-friendly at first glance than solid soaps.

Despite many liquid soaps often being labeled as „particularly creamy“ or „skin caring“, due to their artificial nature liquid soaps are rarely moisturizing. If anything, liquid soaps remove more moisture from the skin than they restore. However, many users of liquid soaps prefer having a convenient pump dispenser and disregard the associated hygienic disadvantages. In fact, the liquid soap’s plastic packaging provides no full protection from bacteria and germs. This is mainly due to the surface of the pump dispenser on which bacteria and germs like to accumulate and multiply. For this very reason there are now sensor-sensitive liquid soap dispensers in almost all public washrooms. 

Flüssigseife, Bürste, Handtuch

Which one is better?

Numerous scientific tests have shown that there is no difference between liquid and solid soap in terms of washing quality and, ultimately, hand cleanliness. Which soap form is the most skin-friendly still seems to be an unsolved question as skin compatibility differs from person to person. Experts advise people with particularly sensitive skin to use solid soap because it contains fewer artificial ingredients and is therefore gentler on the skin. Also, the ecological and ethical arguments for the usage of solid soap are particularly strong.

Yet, it is beneficial to always take a look at the soap’s packaging. This way, you can make sure that the soap was manufactured locally, thereby reducing carbon emission, making the soap more sustainable while also supporting local companies. In addition, read the listed ingredients carefully in order to avoid harmful additives. 

If you still can’t or don’t want to live without liquid soaps, it is recommended to look out for test results. Various test results for the different liquid soaps can be found online.

Regardless of liquid or solid soap: We wish you happy hand washing!

By the way: There is also shampoo in solid form! Find out more about the advantages of solid shampoo.