There are a plethora of reasons to avoid commercial deodorants. With aluminum, toxic chemical fragrances, and parabens; they are a perfect storm. On top of that, the underarms are a very sensitive area to apply toxins to with lymph nodes nearby.
In order to keep this area, and the rest of the body, free from such toxins, it’s a good idea to make your own deodorant. These won’t stop you from sweating, but they can aid in keeping odors to a minimum. This is especially true when the deodorant uses anti-bacterial ingredients such as virgin coconut oil.