Your body is covered with sweat glands because sweating is an essential function that helps us cool down.
There are two main kinds of sweat glands: eccrine and apocrine.
Eccrine glands cover much of your body and open directly on the skin’s surface.
By contrast, apocrine glands occur in areas that contain a lot of hair follicles, like the groin and armpit. Instead of opening up to the surface of the skin, apocrine glands empty into the hair follicle and then open up to the surface.
When your body heats up, eccrine glands release sweat that cools your body. It’s typically odorless, until bacteria on your skin starts breaking it down. Certain foods and drinks you’ve consumed, as well as certain kinds of medication, can also cause eccrine sweat to smell.
Apocrine glands work primarily under stress, secreting an odorless fluid. This fluid begins to develop an odor when it comes into contact with bacteria on your skin. These glands don’t start working until puberty, which is why that’s usually the time we start to notice body odor.
While this is normal, some people sweat more than usual. This condition is called hyperhidrosis. People with hyperhidrosis sweat excessively, especially from their hands, feet, and armpits. If your doctor thinks you might have this condition, there are tests they can do to confirm a diagnosis, ensuring it gets treated properly.
How to treat smelly armpits
Treatment for smelly armpits depends on the severity and underlying causes of the body odor. The odor can be caused by poor hygiene or not using the right products. Or there may be an underlying medical condition that needs to be treated.
Using an over-the-counter (OTC) antiperspirant or deodorant (or a combination antiperspirant-deodorant) daily, after your shower, can help remedy armpit odor. Sometimes you need to try different kinds to see which one works best for you.
Antiperspirants help to reduce the amount of sweat produced by temporarily blocking the pores that release sweat. The less sweat that comes to the surface of your skin, the less odor that results. Deodorants stop sweat from smelling but don’t stop sweat itself. These products are often alcohol-based, turning your skin acidic. This inhibits bacteria from forming — which is what causes sweat to smell.
If OTC deodorants aren’t effective, talk to your doctor about prescription-strength deodorant.
Although many are familiar with Botox for its use in smoothing facial wrinkles, it has several other practical applications. Botox injected into sweat glands decreases both sweating and odor. This is a common treatment for people with hyperhidrosis.
This isn’t a permanent solution, though. The injections only last a few months, so the procedure needs to be repeated as necessary.
How to prevent smelly armpits
There are things you can do to prevent underarm odor from developing in the first place. Showering daily with soap, as well as showering after strenuous activity like working out or playing sports, gets rid of the bacteria and sweat that cause odors.
Wear loose-fitting, breathable fabrics like cotton, linen, and moisture-wicking blends — especially if you sweat a lot. These will allow your body to stay cooler better than constricting clothes made from nonbreathable fabrics.
A 2016 study found that shaving or waxing the armpits significantly reduced armpit odor. This is because cleansing is more effective on shaved or waxed skin.
Since the stress reaction can cause sweat glands to produce sweat, stress management and anxiety-reduction techniques can help you modulate your stress reaction and minimize your physiological sweat response. Find out 16 ways you can relieve stress and anxiety.
Here are some additional DIY life hacks that you can try at home. Find what works best for you, especially during the different seasons.
When to see a doctor
If you’ve used multiple kinds of deodorants or antiperspirants and nothing helps to reduce your underarm odor, talk with your doctor. They can rule out underlying medical conditions and recommend stronger treatments.