What Causes Black Underarm Stains and How to Prevent Them

Dear Home Ec 101,
I have black underarm stains on many of my shirts. That’s right – BLACK. It started happening after we moved to the mountains of western NC where we have well water, but it’s only my shirts – not my husband’s. I’ve tried changing deoderant (though I suspect they all have the same active ingredients) with no effect. I’ve tried scrubbing the stains with various stain removers. Nothing. The stains are on the inside of the shirts – but after a while it shows through to the outside of any light-colored shirts. I’ve never seen anything like it before and – to be honest – it makes me feel like kind of a freak. Can you help?
Funky in Franklin

How to Prevent Black Underarm Stains
Heather says:

Antiperspirants and deodorants are two distinct products, but in our everyday speech we tend to use the terms interchangeably and I have done so throughout this response as a way to help people using search find what they need.

You were on the right track when you tried switching deodorants. If you take a walk down the antiperspirant / deodorant aisle, you’ll notice quite the selection. Most of the antiperspirants / deodorants you see will all have the same active ingredient(s): aluminium chloride, aluminium chlorohydrate, aluminium-zirconium or a combination of thereof. Did you notice something about those three active ingredients? They all contain aluminum.

For most of us the aluminum in antiperspirants isn’t a big deal, it helps us stop sweating from our underarms for a few hours and we go through the day without offending our neighbors. Neat.

However everyone’s body chemistry is a little different, it’s the food you eat, the water you drink, and your genetics. You know how everyone likes to giggle about what eating asparagus does to urine? Well it doesn’t do that to everyone’s. Some people think cilantro tastes like soap -and I cry a little for all they miss. Your quirk is that something in your sweat, is making that aluminum show up on your shirts, lucky you.

Since we’re all special snowflakes the first tip is specific to people, like you, who have dark stains from their deodorant / antiperspirant.

Avoid the aluminum

Try switching to an aluminum free antiperspirants / deodorants I did a search on Amazon that will show you specific brands and labels to look for the next time you head to the store.

On a side note, some people avoid aluminum because they believe that aluminum is the cause of of Alzeheimer’s. That hasn’t been proven, what they’ve found is that people with Alzheimer’s tend to have more aluminum in their brains, this doesn’t mean that the the aluminum was the cause, it just means that it shows up in people’s brains when they have Alzheimer’s. It could be like the way ketones show up in the urine of diabetics, the insulin is absent so ketones show up where they normally wouldn’t. Just because something is there, doesn’t mean it is the cause. (I haven’t done a lot of research lately, but feel free to link to peer reviewed sources, if you want to discuss this point).

You didn’t mention where you moved from. Why do I ask? Well, if you moved from a cooler climate, there is a chance part of the problem is that you haven’t had to use as much antiperspirant as you do now.

Use less antiperspirant.

Antiperspirant works by blocking your pores -I’m simplifying here- once those pores are blocked an extra coat of the white stuff isn’t going to be helpful, it’s just going to rub off on the inside of your clothing. When your antiperspirant wears off and you begin sweat, you’ll have more aluminum hanging out on your shirt to react with your sweat and create that dark stain.

For those of us that don’t react to aluminum, this means we have to remove deodorant build up from our shirts.  You can try to remove the dark stains with the same tips as in that article, but with the chemical change, it may be permanent.

how to remove stains from clothes

Click the picture for more tips!

Additionally, try to let your antiperspirant or deodorant dry completely before putting on your shirt. This will also help reduce the amount absorbed by the fibers of your clothing.

So your homework is to find an aluminum free antiperspirant / deodorant, use less, and try to let it dry before putting on your shirt to prevent future stains.

Got it?

Submit your questions to helpme@home-ec101.com.


  1. Anne on October 26, 2018 at 8:53 am

    My theory on the black/gray stains is that it’s mildew. I, too, live in North Carolina, and it’s very humid here. Mildew spores are everywhere, so they are no doubt in our clothes as well. Underarms are warm and moist, the perfect environment for the mildew to grow.

  2. Darlene D on January 3, 2017 at 9:01 pm

    I am also in Western North Carolina. The mineral in our waters here is Mica. I don’t sweat but my daughter does and has the black stains on light colored clothes and white stains on dark colored clothes. We can’t change the mica but will look into changing the deodorant. I have enjoyed reading all the posts. Very helpful!

  3. Jayne on August 30, 2015 at 9:27 pm

    I have always use one of the non-aluminium deodorants suggested and still have those dark arm pit stains. Any other suggestions?

    • DC on February 21, 2016 at 2:28 pm

      Seconded. I had this for the longest time; then I switched to Trader Joe’s deodorant and the problem went away. TJ discontinued it, though, so I switched to Tom’s… which caused unbearable irritation for me. I switched to Green Tidings (the most popular non-aluminum deodorant on Amazon, and… well, here I am ’cause they’re back. D: )

      • Alistair on June 9, 2017 at 11:06 am

        Yaaas I tried American Providence and I got black stains on my shirt.

  4. Catherine Verney on April 7, 2014 at 8:31 am

    Thank you so much. I also have the same problem. I will try a non-aluminium deodorant.

  5. Juan on March 13, 2014 at 9:05 pm

    Thank you so much! I didn’t know it and now I know how to prevent it.

  6. Jennifer on February 5, 2014 at 11:21 pm

    I am a healthy woman with very healthy sweat-glands(since I turned 12) and I have passed these on to my 14 yr old daughter. We both have to keep Antiperspirants handy for the hot days or else we can’t stand to smell ourselves. I noticed that our shirts were developing stiff black stains on the underarms after moving to the NC mountains. I think the cause may be a combination of our sweat chemistry, the aluminum ingredient our hygiene products, and the mineral content in the water used to clean the close. I have come to this conclusion since the stains don’t appear until after washing and drying them.

  7. Mary on November 18, 2013 at 3:50 pm

    As soon as I saw “aluminum,” I took my son’s light pink shirt with the black underarm stains and applied aluminum jelly to the underarms. Stains gone! I’ll also ask him to use a little less deodorant – he’s very hygienic. 🙂

    • Alyce on April 21, 2016 at 11:58 am

      Ms Mary, I ordered some aluminum jelly and waiting for it to arrive. Can you please please share how you used it (how much you used, how long you let it sit on the stain, and how you laundry it) to remove the black armpit stain? Thanks!!!

  8. Joy on January 12, 2013 at 8:50 pm

    I had/have the same problem. It went away after I had my son and now it’s back after I had my 2nd daughter. I’ve used the same deodorant since I first started using deodorant and I’m 32 so a little over 20 years. I add bleach to every wash and still the stains are getting darker and darker. Idk what to do anymore because this is ruining my clothes.

  9. Donna on September 11, 2012 at 10:29 pm

    Will aluminum cause light stains on dark fabrics as well? I have dark stains on light-colored shirts, and light stains on dark-colored shirts. I haven’t tried the non-aluminum deodorant yet.

  10. Workedforme on August 14, 2012 at 10:45 am

    Are you using pods detergent?  We started getting those black stains a few months ago, sometime after we started using pods.  We just switched back to regular powdered detergent and the stains went away within 1 or 2 washings.  I can’t blame the black stain on antiperspirants – we’ve used them for years and never had black stains before.  I originally put the pods in the soap dispenser and a few months later realized you are supposed to put them in the barrel of the washer.  Even so, the stains didn’t come out after changing where I put the soap.  But reverting to powdered Tide removed all the stains very nicely. 

    • Peggy on June 27, 2016 at 12:10 pm

      Interesting…we used homemade detergent for years then life got busy and I started using Tide. Thats when the black stains began appearing…only on my clothes. Equally interesting is the fact that I had started using an aluminum free deodorant at the same time. Puzzling…

  11. Ronomar on August 13, 2012 at 6:40 pm

    I have the same thing happening with my bras, and don’t know what to do.  Did you ever find out what was causing it or any remedies?

    • annette kendry on September 9, 2013 at 11:03 pm

      This may sound strange but my daughter’s friend only ever drank tequila when they went out with friends and she ruined all her tops due to black underarm stains on them. When she borrowed my daughter;s clothes at times they were always returned with these black stains. However when she stopped drinking tequila the problem went away.
      I removed the stains from the soiled tops she borrowed with dawn dish detergent and gylcerin (worked like a charm.

  12. MANZIMAMA on July 3, 2012 at 12:59 pm

    This is great!  I always wondered why my shirts always get a dark stain under the arms. it is so annoying, it makes all my shirts look old and dirty when they are not.  I’m going to try aluminum free.  Thanks for the tip!!!  Is there any advice on getting out the stains after they have been dried and been there for a while?

  13. Rebecca on May 15, 2011 at 6:07 am

    Very interesting! I didn't know that some people had a hard time with dark sweat stains.

    And yeah, I'm one of those who thinks cilantro tastes like soap. Even just a little bit is enough to ruin a dish for me. 😛

  14. Lisa Reynoso on May 15, 2011 at 1:43 am

    Speaking of natural alternatives, my husband hit on a really good one recently. Get a bottle of tea tree oil from the pharmacy and rub a drop under each arm after bathing. In cooler weather, this will last me 2 days (if it's hot, I shower every day anyway). The idea is that it prevents bacteria growth, which is what is causing the smell in the first place. If you are wearing a tight-fitting top, you should put it on right away after applying the oil so that a little gets on the clothes, or you could get bacteria growing in them even though your skin doesn't smell.

    Of course, this doesn't prevent sweating, but unless you sweat excessively and it shows as wet spots, it's probably not really an issue.

    I've also heard you can do the same thing with grapefruit seed extract. I've never tried it, but since that kills bacteria, it should work. I think the tea tree oil is cheaper, though.

  15. Lucy on May 14, 2011 at 8:48 am

    Hmmm, I get black sweat stains on my bras, under the Girls, not under the arms. I'm sure not putting deo/anti-p there, and I use a non-aluminum one anyhow. My only solution, after many tries with various products, is to toss them when I can't stand them any longer. Any siggestions?

  16. moonablaze on May 14, 2011 at 3:48 am

    note regarding asparagus and pee: everyone's smells, not everyone can smell it!

  17. Bonnie on May 13, 2011 at 8:58 pm

    Just a note regarding those Crystal deodorants: the active ingredient is an aluminum salt, so I don't know that switching to it would help if aluminum is causing the black stains. I use an unscented roll-on deodorant from Home Health called Herbal Magic and found that it works better than any other deodorants I've tried. I think it may be the baking soda in the formula. I agree with the comment to try several until you find one that works for you.

  18. Amanda on May 13, 2011 at 2:53 pm

    I use only all natural deodorant, or none at all. Although I have never had black stains, the yellow stains have stopped since I made the switch.

  19. Kate on May 13, 2011 at 1:48 pm

    I'm disappointed you didn't mention natural deodorants . . . like using baking soda or corn starch or apple cider vinegar. Any one of them is worth a try, especially for someone experiencing a bad reaction to a typical antiperspirant or deodorant. It's easy to find instructions and anecdotes on the web from others who've tried natural methods.

    Personally, the only deodorant I've ever had a bad reaction to at all was an all-natural brand: Tom's of Maine. It would sting and burn my underarms after each use. My husband on the other hand, cannot use products containing aluminum at all and most natural products on the market cause cause him rashes and peeling skin. We both use apple cider vinegar now, which doesn't keep us from sweating (but please remember, sweating is a natural body function . . . antiperspirants inhibit the natural cooling efforts of your body, which many people feel is very dangerous for your health), but does keep you from smelling.

  20. Theresa on May 13, 2011 at 11:15 am

    I've had allergic reactions to several of the more mainstream anti-perspirants and have been using non-aluminum versions for years now (I don't know what the allergy is to, but these don't bother me the way the others do). One thing I have found is that different ones work better than others for different people so if one doesn't work after a few weeks try another one instead of just giving up. The one that seems to work best for most people I know who have a similar problem is the Crystal brand sticks (you can get them at Whole Foods, Amazon and probably other places as well and they last a really long time). The only thing is that the smoother your armpits are the better they work (a lot of guys have problems with them because of this). I only mention this because for a while I was wondering if my only choices were itching (due to the allergy) or being stinky as the summer highs were I live are generally 110-115. Hopefully this helps others who are trying to avoid aluminum deodorants, etc. for whatever reason.
    My recent post this moment

  21. Milehimama on May 13, 2011 at 10:33 am

    I have the same problem- but only on my maternity shirts! I guess the pregnancy hormones must affect my sweat.

    I've used those natural crystal deodorants in the past, and they worked for me. Guess I'll have to go back to that.
    My recent post A Little Dark In Here- Prudently Prepared

    • Lyndsi on May 24, 2013 at 12:59 pm

      most crystal deodorants still have Aluminum in them!! You have to be very careful! Read all of your ingredient labels!

      • Bailey on November 10, 2015 at 1:39 pm

        The Crystal deodorant contains potassium alum or potassium aluminum sulfate. This is a naturally occurring mineral that is made of larger molecules that aren’t absorbed by the skin like other aluminums found in most deodorants.

  22. Jess on May 13, 2011 at 10:10 am

    Point of info if you are switching to non-aluminum (which some do for breast cancer fears as well). It takes about 2 weeks for your body chemistry to adjust to the new deod/antip. But once it does, the non alum ones will work as well as the old ones, except in heavy (running/biking or hot summer situations). I recommend for those two weeks carrying the deodorant with you as well as wipes – baby wipes, handwipes – and wipe clean and reapply whenever needed.

    • Lyndsi on May 24, 2013 at 12:58 pm

      Check out the deodorant by Ava Anderson Non-Toxic. There is no aluminum, it is all organic and YOU CAN use in running/biking/ marathon/hot summer situations and it works!!!!!!!! Check out their facebook page for more info – http://www.facebook.com/avaandersonnontoxic

      • Karen on October 18, 2015 at 11:47 pm

        We use Ava Anderson deodorant in our family and I was looking up this topic because my daughter has some awful stained shirts and she only uses the Ava deodorant. Not sure how to clear them up or better yet prevent them. Not sure what is causing it since there is no aluminum.

  23. MaggieM on May 13, 2011 at 9:21 am

    I don't get dark stains but I do have trouble with yellow pit stains (and it's way worse on my right underarm, isn't that weird?). It was incredibly frustrating/annoying until I learned about the powers of vinegar. Now I keep a spray bottle of straight-up, household strength, white vinegar next to my stain spray at the washing machine. ALL of my shirts, but especially light colored and white ones, get a spray of vinegar on the pits before washing. It has made a world of difference. Oxy clean (and the like) works great, too.

  24. Kim on May 13, 2011 at 8:22 am

    I had the same problem with a couple of white shirts. After washing (but before drying) I placed the shirts into a small dishpan with oxi clean added. I let them soak several days and the stains became much lighter.

  25. Marsha on May 13, 2011 at 7:30 am

    Good answer. As a fellow Family and Consumer Scientist, I appreciate your work so much!

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.