First off, you'll notice all the "Natural" brands are just "deodorant" because there's no known safe & natural "antiperspirant." Only aluminum is approved in most world markets, including the USA, as a safe antiperspirant - that actually prevents sweating and odors rather than trying to only mask or neutralize them after sweating occurs. Most antiperspirant brands are also deodorants, but products labeled deodorant are typically NOT antiperspirant and this is especially the case for anything claiming to be Natural.
I notice tons of ads now for "aluminum-Free deodorant" and it's bullshit basically. I researched it and it's similar to crap people have against artificial sweeteners and eating non-organic food. Scientists have never linked aluminum antiperspirant use to health detriments.
Good Vice article on the fear-mongering
https://tonic.vice.com/en_us/article/mgyx54/the-final-word-on-whether-antiperspirant-is-safe
Good summary of research
https://www.webmd.com/breast-cancer/features/antiperspirant-facts-safety
Good explanation of why Natural Antiperspirant doesn't exist
http://nymag.com/strategist/article/natural-antiperspirant-explainer.html
EDIT: there's stain-Free varieties now so that's irrelevant
I notice tons of ads now for "aluminum-Free deodorant" and it's bullshit basically. I researched it and it's similar to crap people have against artificial sweeteners and eating non-organic food. Scientists have never linked aluminum antiperspirant use to health detriments.
Good Vice article on the fear-mongering
https://tonic.vice.com/en_us/article/mgyx54/the-final-word-on-whether-antiperspirant-is-safe
Good summary of research
https://www.webmd.com/breast-cancer/features/antiperspirant-facts-safety
Good explanation of why Natural Antiperspirant doesn't exist
http://nymag.com/strategist/article/natural-antiperspirant-explainer.html
EDIT: there's stain-Free varieties now so that's irrelevant