Nasty Chemicals
There are way more unnecessary chemicals in body wash than in soap. Things like phthalates, parabens, formaldehyde, and sulfates, all of which can mess with the way your body produces hormones or the ways your cells replicate, which can cause cancer. Many other ingredients like fragrance and colors in body wash may also cause skin irritation. That seems counterintuitive, no? Shouldn't the soap remove things that irritate your skin?
Fragrance
The term "fragrance," for now at least, is a term that allows companies to keep their signature scents as proprietary secrets. It means they do not have to disclose all of the ingredients in their products. Many of the ingredients that have been known to fall under the term fragrance have been linked to various diseases including cancers. Be aware, unscented and fragrance free are not the same. Unscented products may still include chemicals used to mask the scent of other ingredients in the product.
Cost
Bars of soap are less expensive than body wash and serve the same purpose. Even if you get fancier bar soap, it will probably still save you money.
Luxury
You can get soap sock things that will help make the soap lather up just as nicely (if not more luxuriously) than body wash on a loofa. This will also help with the slipperiness and mess on the shelf. Another option is to buy felted soap (available in many places), or if you are feeling crafty, you can make your own. This is just one of many tutorials online.
Beautiful Smells
If you do still want your soap to smell pretty, opt for soaps that include natural essentials oils like lavender, peppermint, or rose. These won't be counted under "fragrance" and are safer because they occur naturally in the plants.
Waste. While oftentimes the plastic bottles that body wash comes in are recyclable, recycling for plastic isn't perfect. A lot of plastic still gets into our waterways, which can come back to us in ways we don't want.
So, for your health, consider making the switch from body wash to bars of soap. It will save you money, and protect you from the various chemicals that might lead to cancer and irritation later in life. Hopefully these facts will be enough to convince you to give bar soap another chance.