How Body Soap Works

With body soap options including bar soaps, liquid soaps, body washes, antibacterial soaps and herbal products, it can be hard to choose the right one. See more pictures of unusual skin care products.

Buying body soap is nothing new. You've probably been doing it your entire adult life. It's just one little item on your shopping list that should take you a split second to grab while you're at the store. But if you've wandered up and down the soap aisle recently, you probably know that trying to pick out the right kind of soap from among the vast selection of products can be as difficult as getting a good lather without any water.

Body soaps come in many forms with varying ingredients. Gone are the days when you just grabbed whichever soap your family used to use. Today there are bar soaps, liquid soaps, shower gels, soaps for specific skin types, antibacterial soaps and even soaps infused with herbs. Deciding which one to get is enough to make you want to throw in the towel. You definitely don't want to buy the wrong soap and end up with an allergic reaction or case of contact dermatitis, which is a red inflammation of the skin [source: Mayo Clinic].


Let's get down to the basics. Divert your eyes from the "20 percent more free!" stickers, the soap and lotion combo pack and the cute travel soaps wrapped in tropical patterned paper. Take a moment to think about what you need from a cleansing product. Body soaps are meant to cleanse your body and remove dirt and excess oils that can contribute to unpleasant odors. They are also intended to help wash away bacteria that can lead to infection. Some soaps are even formulated to contain moisturizers. Simply put, body soaps should leave your skin clean, smooth and hydrated. But choosing the soap that's best for you can be overwhelming because there are so many different kinds out there.

If the thought of searching the soap aisle scares you, get ready to wash your worries away. Read on to learn about the chemistry behind body soaps and what each type of soap has to offer.


Body Soap Chemistry

Maybe you have several different kinds of body soap sitting around your house. There's the old standard bar of deodorant soap that usually sits on your shower shelf, the pump of antibacterial soap next to the kitchen sink, the shower gel and loofah sponge you received as a gift, and that small bottle of body wash from the hotel you stayed at during your last vacation. All these products have at least one thing in common: They clean. The difference is in how.

Water alone can wash away dirt from your skin by sheer force, but because water doesn't mix with oil, it is ineffective in removing oily buildup [source: Ophardt]. In order to get rid of excess oils from your skin, soaps have to have bonding power. True soap is made up of fatty acids, which contain a chain of connected hydrogen, carbon and oxygen atoms. One end of this chain is lipophilic - it is attracted to oils. The other end of the chain is hydrophilic, or attracted to water [source: The Soap and Detergent Association]. When you lather up, the lipophilic ends of the molecules pick up the grease and oils on your skin. When you rinse, the hydrophilic ends of the molecules follow the water, letting you rinse the soap molecules -- and their attached impurities -- away.


When picking out your body soap, you'll want a product that can wash away the dirt and extra oils from your body. However, you'll also want a soap that doesn't strip away the natural oils that should be in your skin. Removing too many of the oils from your body will leave your skin dry, flaky and irritated. Ideally, your body soap should remove the oils you don't need and leave the moisturizing oils behind.

Chemistry lesson aside, if you're ready to lather up, read on to find out what you can expect from bar soaps.


Bar Body Soap

Each type of body soap has pros and cons, which is why there are so many choices on the shelves. Your first job is to decide which properties you want in your soap -- specifically, whether you want it to be a bar or liquid.

One of the benefits of bar soap is that it's relatively cheap and easy to store in the bathroom. However, you have to be careful about ingredients. Some bar soaps are designed to really clean and strip away dirt and grime. These strong soaps might be great at removing dirt and grease after a day of working in the garden or under the hood of the car, but they aren't the best to use for repeated hand washings or for cleansing your face. Harsh bar soaps can be very drying to the skin, especially if they contain sodium lauryl sulfate (SLS) [source: Bruno]. It's best to limit how often you scrub down your face and body with strong soaps that can dehydrate the skin.


The good news is that bar soaps come in a variety of formulas. Some are specifically designed to be mild and moisturizing, and they contain ingredients that won't strip away the oils your skin needs. Moisturizing bar soaps are ideal to use for your face and body. You can also find bar soaps that double as facial cleansers. These soaps have been formulated for the delicate skin on your face and may contain acne-fighting ingredients.

When you select a bar of soap at the store, however, read the label to check for ingredients that can cause skin irritation. If you have eczema or are sensitive to perfumes or dyes, choose mild soaps that are fragrance free to lessen your chances of itchy inflammation [source: Mayo Clinic].

Now that you've considered the scrubbing power of traditional bar soap, read on to find out what liquid body soap has to offer.


Liquid Body Soap

Another common type of body soap is the liquid variety. Liquid soaps come in many forms, including hand soaps, facial soaps, gels and body washes.

Liquid body soaps are not necessarily better or worse than bar soaps, so choosing one over the other is mostly a matter of personal preference. Some people prefer liquid soaps for the hands and face because they are generally milder and less irritating to sensitive skin than some types of bar soaps. Or if bar soap tends to leave your entire body feeling dry and itchy, a liquid body wash that contains moisturizers might be your ticket to silky, smooth skin. If you're thinking of giving liquid body soap a try, here are some things you should consider.


Get a liquid body soap that contains ingredients to help seal and lock in the skin's natural moisture levels. A body wash that contains glycerin or humectants such as sunflower oil and soybean oil might soothe itchy, dry skin [source: Bruno]. Moisturizing body washes can also work for the hands and face and for people with sensitive skin.

If you have oily skin that is prone to breakouts, liquid soaps that contain salicylic acid or benzoyl peroxide can help [source: Bruno]. These ingredients can exfoliate dead skin cells and unclog pores to promote clean and healthy skin.

If you're looking for added exfoliating power to remove dead skin cells and stimulate new cell growth, consider getting a body scrub with beads, sugars or fruits. It's best to gently rub these soaps onto your skin instead of forcefully scouring yourself clean.

If you think choosing between bar soap and liquid soap is a piece of cake, there are still specialty soaps to consider. Keep reading to see whether any of them might be for you.


Specialty Body Soaps

Depending on whom you ask, you'll get a different definition for what makes something a specialty body soap. However, to make it easier, consider some points about other products that can be lumped into the "specialty" category.

Soaps made with glycerin or sugars are usually transparent and are designed to be less drying than soaps made without these products. If you've had issues with dry skin, you might consider a glycerin- or sugar-based soap.


Certain beauty bars might contain sodium lauryl isethionate instead of the more dehydrating sodium lauryl sulfate. Lactic or citric acid, which is often added to beauty bars, can lower the pH level from 9 to 10 down to a range of 5 to 7, which can also help protect the skin's natural moisture level [source: Draelos].

Botanical, natural or herbal soaps contain herbs, essential oils and plant extracts. Common examples of these kinds of ingredients include green tea, lemongrass, ginger, sea salts, lavender and peppermint. You can often find soaps that contain these natural ingredients in boutiques or on the Internet. If you have had reactions to ingredients in traditional soaps, you might find the natural ingredients more suited to your skin type, but know that even natural products can still cause irritation or allergic reactions.

Perfumed and colored soaps contain extra ingredients to rouse your senses, but they might leave you more than just smelling like a rose. One of the most common reasons people suffer from contact dermatitis or other similar skin problems is because of their soap [source: Mayo Clinic]. Look specifically for fragrance-free and dye-free soaps if you are having problems with skin breakouts or irritation.

If you're not completely overwhelmed with choices and ready to grab whichever soap is closest, you still have one last point to consider. Read on to find out whether antibacterial soaps are worth the money.


Antibacterial Body Soaps

When you think of antibacterial soaps, liquid hand soaps most likely come to mind. You wash your hands several times a day, so why not boost up the germ-fighting power of your soap? After all, cold and flu season seems to last all year long.

Before you load up your cart with germ-busters, however, remember that the effectiveness of antibacterial soaps compared with that of regular soaps in everyday use has not been proven [source: National Institutes of Health]. However, antibacterial soaps are sometimes useful when it comes to cuts, abrasions and some skin disorders, because they can slow the growth of bacteria on the skin.


If you're considering getting a deodorant soap, those with antibacterial properties are designed to kill off odor-causing bacteria [source: American Academy of Dermatology]. This sounds great for those needing an extra breath of fresh air from their soap. Keep in mind, though, that deodorant soaps can be harsh and drying, so be on the lookout for changes in your skin's chemistry.

Soaps marketed as acne-fighting also come in antibacterial forms, which shouldn't be surprising since bacteria are a leading cause of acne. As long as the cleanser is mild and does not aggravate your breakouts further, there is no need to worry. Remember that acne-prone skin is often more sensitive to irritants, so keep your cleansings gentle and use warm water.

When it comes right down to it, you're still going to have to search the cosmetics aisle for the perfect soap for you. Hopefully you're ready to grab a package and read its label like a pro. You can also explore the links that follow to learn more about the ever-growing world of body soaps.


Lots More Information

Related HowStuffWorks Articles


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  • American Academy of Dermatology. "Dry Skin & Keratosis Pilaris." (Accessed 8/25/09)
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