crystal deodorant

Q. Would you please comment on the safety of alum as a deodorant? I think it is the ingredient in many “Crystal” antiperspirant products.
A. We have heard from lots of readers that they gave up aluminum-based antiperspirants because of a fear of either Alzheimer’s disease or cancer. Here are just a couple of examples:

“The women in our family have been using Crystal roll-on for some time, as we’ve been avoiding aluminum and paraben for years and we find that it works well.”


“For more than 10 years I’ve used deodorant-only products, because someone warned of a cancer risk. It’s a bit hard to find, but I found a crystal roll-on product that is fragrance, paraben and aluminum chlorohydrate free. Seems to work well. If I hadn’t just bought a new bottle, I’d try the Graedons’ Milk of Magnesia roll-on deodorant.”


“Have started using Crystal roll on deodorant which is paraben free and is a natural product. It is made from mineral salts and is also hypoallergenic and safe for the environment.”

Crystal deodorant sounds like the ideal solution for avoiding aluminum in an antiperspirant. There is one problem, however. Many of the manufacturers of such products are very cagey about the ingredients in their “natural” crystal deodorant products. There is no doubt that such products are natural, since aluminum is a mineral found in nature. You will sometimes see the word “alum” or potassium alum as the main ingredient.
The online Merriam-Webster dictionary defines alum as:

“a potassium aluminum sulfate KAl(SO4)2·12H2O or an ammonium aluminum sulfate NH4Al(SO4)2·12H2O used especially as an emetic [causes vomiting] and as an astringent and styptic [to prevent bleeding].”

Alum has been used for a very long time in reservoirs to clarify water. That is, it helps suspended particles settle to the bottom so they can be removed. It has also been used as a remedy for canker sores and in a styptic pencil to stop bleeding after shaving. That said, there is no doubt that alum contains aluminum, often hydrated potassium aluminum sulfate (potassium alum). Anyone who thinks that using a natural crystal deodorant eliminates aluminum is kidding herself.
Is the aluminum in natural crystal deodorants dangerous? That is a question that remains unanswered. How much aluminum is absorbed from delicate underarm tissue? No one has a good answer. If this aluminum is absorbed, does it pose any health risk?
An article in the Journal of the National Cancer Institute (Oct 16, 2002) concluded that there was no connection between use of antiperspirants and the risk of breast cancer. More recently, though, a study suggests that aluminum compounds can change the way breast cells divide, even at low concentrations (Journal of Applied Toxicology, online, Jan. 6, 2012). The authors of this research conclude: “Our observations do not formally identify aluminium [British spelling for aluminum] as a breast carcinogen, but challenge the safety ascribed to its widespread use in underarm cosmetics.” There is also research to suggest that aluminum concentrates in breast tissue, possibly from exposure to aluminum-containing antiperspirants (Journal of Applied Toxicology, April, 2011).
A study in the Journal of Inorganic Biochemistry (Nov. 2011) points out that: “The human breast is exposed to aluminium from many sources including diet and personal care products, but dermal [skin] application of aluminium-based antiperspirant salts provides a local long-term source of exposure.” These researchers note that nipple aspirate fluids have been shown to contain aluminum at higher levels in breast cancer patients than from healthy control subjects “providing evidence of raised aluminium levels in the breast microenvironment when cancer is present.”
A thoughtful review of this entire topic was published in Best Practice & Research. Clinical Endocrinology and Metabolism by a British oncology professor. Some of the comments include:

“Several components of cosmetics have genotoxic properties, including the aluminium salts..”
“Dermal absorption of topically applied antiperspirant aluminium salts has been demonstrated through intact mouse skin and and the skin of the human underarm. Aluminium in the form of aluminium chloride or aluminium chlorhydrate has been shown capable of interfering with the function of oestrogen receptors of human breast cancer cells both in terms of ligand binding and oestrogen-regulated gene expression.”

That is, these compounds may act as hormone disruptors.

It will probably take many more years to resolve the controversy about any relationship between aluminum and breast cancer. In the meantime, people who seek to avoid aluminum in their armpits will probably want to look beyond crystal-type natural deodorants. Many people find that milk of magnesia applied to the underarm helps against odor, so that may be an attractive alternative. There is more information about this here.

Join Over 100,000 Subscribers at The People's Pharmacy

Each week we send two free email newsletters with breaking health news, prescription drug information, home remedies and a preview of our award-winning radio show. Join our mailing list and get the information you need to make confident choices about your health.

  1. Dustin

    Also you can check for your specific products here:

    PLEASE SHARE THAT LINK!! You can search nearly any health products! For example my Crystal deodorant rates a 1 (safe) :

    Compare that to something bad rating of 4:

  2. jo

    Why milk of magnesia? Just mix coconut oil with baking soda. And add some arrow root powder. and then some sage oil. Perfect deodorant! Cheap, and you can mix other etheric oils for different different fragrances

  3. Karen

    “there is no doubt that alum contains aluminum, often hydrated potassium aluminum sulfate (potassium alum). Anyone who thinks that using a natural crystal deodorant eliminates aluminum is kidding herself”

    What I can’t figure is why brands list Aluminum Free on deodorant that clearly contain Aluminum. It’s not being honest in product labeling. As far as I can research Mineral salts contain Alum and Alum has Aluminum in it. It’s not just the Crystal either, dozens of other brands mislabel too. Use of Potassium alum. is to inhibit bacterial growth and it’s cheap.

  4. LC

    I use Milk o Magnesia occasionally. But the biggest factor for not having bo in my armpits seems to be using castille soap. I shower with some and I don’t have to use deo. If I try regular soap, (animal based?) then I quickly smell if I don’t use deo… Coconut is antibacterial so maybe that’s why Kirk’s works so well…

  5. C.s

    Do you drink it or apply it??
    People’s Pharmacy response: You apply it to the underarm.

  6. zay h

    hi i am actually using the crystal deodorants thinking it is safe. My chemistry knowledge is very poor. I wish to know more about that magnesium thing and where to buy it. Thank you

  7. NBF

    One way to apply milk of magnesia is with a cotton ball. The brand name I used was Phillips Milk of Magnesia. I don’t know if the kind I used contained saccharin sodium, because I switched to the People’s Pharmacy MoM after reading in another People’s Pharmacy article ( that “most of the milk of magnesia that you buy over the counter contains bleach (sodium hypochlorite) as a preservative”.
    I tried opening the People’s Pharmacy MoM roll on and putting it into my spray bottle. It clogged badly and sprayed so widely that it often landed on unwanted areas near my underarms. Then I started using the roll on applicator and was able to target the underarm area much better.
    I went through a stressful time, and found that the People’s Pharmacy MoM was not working as well for me as it originally had. I theorized that the odor-causing bacteria had become resistant to MoM or that the absence of the sodium hypolchorite (bleach) may the deodorant less effective. This seems plausible since bleach kills bacteria.
    Now I alternate the People’s Pharmacy roll-on MoM with a deodorant purchased at my local health food store which contains ethanol, purified water, and lavender oil. This combination is currently working satisfactorily for me.

  8. L

    I am also sick of aluminium and now finding out aluminium is in crystal deodorants too I’ve bought the milk of magnesia from USA and am about to start using it (I’m in the UK)! It’s just a bottle so how do I use it if I don’t have a sprayer yet do I just put some under my arm?
    Also I’ve noticed the blue bottle fresh mint, has saccharin sodium and I’m not happy about this ingredients so where did you get your brand name one from what do I type into google to get the brand name one to come up please?
    Should have ordered the original?
    I’m excited to see if this actually ensures I don’t smell so I’m trying the mint one and if it works I then must get the original or it defeats the purpose of staying away from aluminium if using saccharin sodium as salt isn’t great for the body in too high doses and also this is another toxin potentially so want to be sure what we put under arms is all chemical free!
    Looking forward to your answers and I’ll let you know if the mint one at least stops any smell and then if it does work on a chemical free one!

  9. NBF

    I like a using a spray type deodorant, so I bought milk of magnesia and put it in a tabletop mister with a clog free filter. I shake before spraying and it works like a charm! I bought brand name milk of magnesia because I noticed that generic brand contained additives I did not want. I ordered the mister online.

  10. Sue B

    I’m glad I read this post! Thank you. For many years I’ve used the crystal deodorants, believing they were safer than the usual deodorants, in particular that they were free of aluminum. The first brand of crystal deodorant I bought listed the ingredient “mineral salts” on the label (that’s all). Of course, my knowledge of chemistry is poor, so that sounded OK to me.
    Now I’ve thrown out what I had and bought the milk of magnesia roll-ons from People’s Pharmacy. I only wish I’d known how deceptive the crystal businesses were–all the money I’ve spent over the years for something that turned out to be false…

  11. Sue

    Switched to MOM a few years ago and love it. No more odor! You have to get used to the damp feeling but for odor it works better than any commercial deodorant I tried. I buy the generic brand in the big bottle. It does not stain clothing either.

  12. Lulu

    I recently ordered some milk of magnesia (Gradens) deodorant; it was almost $10 with shipping. I think the roller was stuck because it took quite sometime to get any to come out.
    It definitely does not work as well as the milk of magnesia from the bottle. You can get it from CVS or Walgreens for less than $2. It definitely does work better than Secret or one of the other brands off the shelf.
    We are very disappointed you had trouble with our MoM deodorant. Here is a possible fix:
    Defective Roll-On roller
    So sorry you had this problem. Would you please try this procedure:
    1. Shake well.
    2. Hold container vertically under hot running water.
    3. While holding under the running water rotate the ball clockwise several turns with the thumb and forefinger.
    4. When ball is rotating clockwise freely under running water rotate ball ended over end, i.e., like one typically does when applying to underarm.
    We think that will solve the problem, but if it does not, please let us know if you prefer a replacement or a refund.

  13. PK

    Mine says “No Aluminum Chlorohydrate” while the ingredients state the presence of Potassium Alum. What gives?
    Which is which, or are they both potentially dangerous?
    People’s Pharmacy response: Both compounds contain aluminum, but they are different compounds.
    We don’t yet know for certain how dangerous aluminum may be, but many people prefer to avoid it on the precautionary principle.

  14. LF

    Crystal deodorants never worked for me.
    Milk of magnesia (for me, anyway) only works on odor, but does not control perspiration.
    You are quite right that milk of magnesia is not an antiperspirant. Many people believe it does help control odor through a mechanism that has not been identified.
    The FDA distinguishes between antiperspirants (classified as drugs) and deodorants, which are more cosmetic in nature. To advertise a product as an antiperspirant it generally has to have aluminum in one form or another. Aluminum chlorohydrate is a very common ingredient that the FDA approves of because it does help reduce perspiration.

  15. susan

    The best deodorant I have found anywhere is simply lemon juice. I’m surprised I’ve never seen this mentioned.

    • Lars

      I think lemon juice must be good. Read in an old Swedish book saying that removing sweat stains should can be done by first applying a solution of ammonia, rinsing, then 5 percent acetic acid solution (vinegar), finally rinsing.
      I think the acidic condition will keep the natural bacteria in our armpits happy, and the smell producing bacteria under control.
      When I had to give up inefficient deodorants, I tried vinegar, and it worked. But lemon juice feels and smells better.

  16. NBF

    My Thai Crystal Deodorant Mist says “Aluminum Free” right on the bottle. Can I trust it?

  17. M

    Remarks-Chemistry formula should kSo4& AlSo4 or di Salfate. Both salt are mono. K & Al can’t exists together without di sulfate.

  18. betty

    They might be safe but they sure don’t work. (for me anyway). I had to stay away from people the one day I used it, and apologize and explain why I walked away from them. I told them I had “deodorant failure’ and suggested they never bother to try it.

  19. Michael R

    I tell you, the milk of magnesia Graden deodorant really works, no kidding.
    I have never smelled either of them! ha ha.
    Really, it works and is pleasant to use.

What Do You Think?

We invite you to share your thoughts with others, but remember that our comment section is a public forum. Please do not use your full first and last name if you want to keep details of your medical history anonymous. A first name and last initial or a pseudonym is acceptable. Advice from other commenters on this website is not a substitute for medical attention. Do not stop any medicine without checking with the prescriber. Stopping medication suddenly could result in serious harm. We expect comments to be civil in tone and language. By commenting, you agree to abide by our commenting policy and website terms & conditions. Comments that do not follow these policies will not be posted.