I kept seeing posts about using some deodorant crystal stick that's all natural and supposed to be great. I bought one. It was ok, but I felt sticky and damp. I don't think I smelled great, either. I tried this before going the baking soda route. It wasn't for me. Supposedly the stick lasts at least a year, and it was only $6. Not as cheap as baking soda, but I didn't know about baking soda then.
One day I thought I'd try them both at once. DON'T DO IT!!! Something happens chemically. There was a burning sensation and I smelled something like ammonia almost immediately. I washed off very quickly. I hate ammonia, and certainly don't want to smell like it or having it burn my pits!
I knew not to mix cleansers, but....
Just a warning to anyone who may want to mix something.
I'll be trying baking soda with corn starch this week and I'll let you know how it goes. I'm certain there's no strange chemical reaction with those two. :)