Internal factors, like what you're eating, and external factors, like your environment, can impact how well your deodorant works. Increased humidity and altitude affect your “BO” profile, not just how much you sweat but also your microbiome and how it reacts to sweat.
The overall conclusion is that your armpits have not become immune to anything in the deodorant you use. Rather, your skin microbiome has changed with the passage of time. In fact, many things can change how your armpit behaves that range from diet, to stress and hormones.
Your skin has more time to absorb the compounds and work effectively. If you do experience additional underarm odor, try switching your deodorant or antiperspirant. You can try clinical-strength or prescription options, or natural deodorants.
Body odor is caused by a mix of bacteria and sweat on your skin. Your body odor can change due to hormones, the food you eat, infection, medications or underlying conditions like diabetes. Prescription-strength antiperspirants or medications may help.
Shower More Frequently
Infrequent showering can cause bacteria to build up on your skin. Shower at least once a day (or every morning and night) and scrub your extra-sweaty areas with a scent-free, antibacterial bath soap. Stay away from strongly scented soaps, which can make your armpits smell worse.
Using warm water and anti-bacterial soap will help kill off bacteria that lives off your sweat. It may mean taking more than one shower a day, or just a quick clean at the sink with soap, a wash cloth, and warm water.
Baking Soda
You can take a small amount of baking soda and mix a little bit of water to form a semi-solid paste. Apply this paste to your armpits and allow it to dry. After it dries, wash it off. This might prove to be a good remedy for smelly armpits.
The best way to prevent smelly armpits is to wash daily and after sweating. Using antiperspirant or deodorant and shaving the armpits can also help. Avoiding alcohol and certain foods, such as onions and garlic, will also help prevent smelly armpits in some cases.
"Perspiration levels are not as high compared to daytime and usually the 'deodorizing' is most important during the daytime. While using it occasionally at bedtime is not harmful, use of deodorants around the clock may be an additional source of unnecessary irritation to the skin."
“Depending on your body and what type of deodorant/antiperspirant you're using, you may not need to apply every single day,” explains Dove dermatologist, Alicia Barba, MD, in Miami. Some antiperspirants are made to last 48 hours, which means daily application isn't essential.
Yes, like most personal care products, deodorant is designed to have a long shelf life. But once you've opened it up and started using it, you'll want to use it up within a year or let it go. And if you notice your expired deodorant isn't working as effectively as when you first bought it, it's time for a new one.
What causes the unpleasant smell is the bacteria that build up on your sweaty skin and react with sweat and oils to grow and multiply when sweat reacts with bacteria on the skin. These bacteria break down proteins and fatty acids, causing body odor in the process.
Less body odor
When you remove hair under the armpits, it reduces trapped odor. A 2016 study involving men found that removing armpit hair by shaving significantly reduced axillary odor for the following 24 hours. Similar results were first found in a 1953 paper .
Shower daily and wash your underarms with an antibacterial soap (consider showering twice a day if you sweat excessively) While in the shower fill your hand with hydrogen peroxide and splash and rub it into each of your underarms.
Research has found that the salts in antiperspirants can cause an imbalance of bacteria. The aluminum compounds kill off the less smelly bacteria, giving the smellier bacteria more opportunity to thrive, causing more body odour.
Sweating and body odor are common when you exercise or you're too warm. They're also common when you're feeling nervous, anxious or stressed. Unusual changes in sweating — either too much (hyperhidrosis) or too little (anhidrosis) — can be cause for concern. Changes in body odor also may signal a health problem.
For those wondering, “How much deodorant should I put on?” We recommend 2-3 swipes under each arm for the best results. If you find that residue is transferring to your clothes, it's likely that you're applying too much.
Antiperspirant is most effective when applied to clean, dry skin. If you use it in the morning right after your shower, your skin might be too wet to absorb the formula properly. If you apply it when you're rushing out the door, your antiperspirant may not have enough time to block your sweat glands.