Why Does Only One Armpit Smell more Than the Other (is this Sign of Illness?)

Every living individual is certainly sweating as it is a natural response when the body begins to rise in temperature. Sweating is started from increased activity of Sweat Glands, which react when there is a change in body temperature. Its purpose is for preventing the damage and overheat over the body.

However, people also develop fluctuating conditions or performing highly physical activities that result in overreactions of the sweat glands, which eventually the excessive sweating occurs.

Individuals with excessive sweating commonly have a similar problem, either women or men they potentially have the underarm odor due to excessive sweating. It is not surprising because the amount of sweat in the armpit can trigger the growth of bacteria that cause underarm odor.

People who suffer from this problem will certainly lose their face in public; moreover, they can also lose their confidence and find it difficult to move freely in their social environment, especially if both armpits emit a pungent odor, which results in someone completely isolated from his/her social circle.

However, this condition is not always the same, in which there are times when certain people also experience one armpit has more odor than the other. If you experience this unusual situation, you may also be wondering how comes only one armpit smells more than the other, either right or left armpit, it may always result in a popup question “is this a sign of illness?”

In fact, you also need to be aware that many individuals around the world also experience a similar problem to you, and thus, you are not the only person with this underarm oddity in the first place. For most people, or probably you too, the right armpit usually smells more than the left one.

Before we proceed to find out why only one armpit smells more than the other, it’s better to understand in the first place why our underarms can have a stinging smell. Therefore, by the end of this article, you can also know the reason of one of your armpits is smellier than the other and why this is really happening.

Why do My Armpits Smell?

Offensive odor emanating from the armpits occurs when your body releases excessive sweating. Sweat or often called Hidrosis is derived from the Greek language, so excessive sweating can also be referred to as Hyperhidrosis. There are two types of hyperhidrosis, the first one is Primary Hyperhidrosis, which means that the hyperhidrosis or heavy sweating occurs without any underlying medical causes.

The primary one occurs when your body releases too much sweat as a result of an overactive condition of the nerves responsible for the sweat glands, which eventually draw more perspiration even when it is not required. Hereditary factor becomes the common cause of primary hyperhidrosis.

The second one is Secondary Hyperhidrosis, occurring when it is associated with certain underlying medical conditions. Several medical conditions that may cause excessive sweating including; HIV/AIDS, Diabetes, Fever, Hyperthyroidism, Leukemia, Gastritis, Obesity, Stress, Malaria, Generalized anxiety disorder, etc.

However, heavy sweating is not enough to make your armpits smell. There is still another cause that triggers the onset of underarm odor, which is known as Bacteria. Either bacteria or sweat, the two of which form a partnership that turns your armpits into a smelly zone.

The human body has at least more than 4 million sweat glands scattered throughout the body. The name of the sweat glands taken from the primary function of these glands, which responsible to produce or release perspiration (sweat).

When you engage in physical activity, or the atmosphere around you turns in a hot condition, your sweat glands will release more sweat as a result of your body temperature gets warmer.

One part of your brain called Hypothalamus (a part of the brain which maintaining Homeostasis, which is, to keep the body in a stable and constant condition), responding to different types of signals from any environment, whether external or internal, including responding to body temperature, hunger, blood pressure and hormones.

The hypothalamus delivers a command to the nerves which responsible for the sweat glands to release sweat when the body temperature gets hotter. Sweat has a purpose for making the body to be cool, thus sweating is actually very important for the body as it keeps the body temperature away from an overheat condition.

Regardless of its main function as a body cooling agent, perspiration also has the potential to leave other minor problems such as body odor and coloring of our clothes. However, as explained earlier that sweat alone is not able to make armpits to be smelly. It takes the role of bacteria to promote underarm odor, as either sweat or bacteria, both are the major causes of armpits odor when they work hand in hand.

Nearly trillions of bacteria can be found in the human body, and some of them live and breed in the armpit, because of its moist and hidden nature. Bacteria that stay in your armpits can release the odorous Organosulfur (Thioalcohols) compounds within a certain time. It happens because the bacteria feed on the sweat molecules in the individual’s armpits.

Therefore, the offensive smell emanating from the armpits is actually an organosulfur compounds released by a number of bacteria absorbing the sweat molecules. This condition is sometimes exacerbated by the fact that the armpit is a hidden place of the body and sometimes have a lot of hair growing on it so that the armpit is getting moist and blocking the air flow in the armpits.

Why Does One Armpit Smell Worse than the Other?

Now that you already know how the process of the emergence of underarm odor. Let’s move on one step further, why one armpit is smells worse than the other.

So now you come home from your daily work or regular physical activity at the end of the day, walk into your room and realize that you smell bad, and oddly you notice that your right armpit odor is worse than the left one. Then what would you do next?

A few moments later you may also realize that there are certainly many reasons why this unusual situation occurs. That’s what brought you here, now you may find a few things related to your current situation that you can identify from the following description.

  1. No Two Body Sides Identical

  2. The first thing you need to understand is that our body is not one hundred percent identical between left and the right side, which means that what happens on the right side may not happen on the other side. So even though everyone has two armpits, it does not mean that both have similarities in terms of the number of bacteria and the amount of sweat they can produce.

    Some individuals may have more sweat and bacteria on their right armpit, than on the other side, and the other way around, and it’s just how your body develops. Thus the highly active the sweat and bacteria in one armpit, the more likely your armpit produces a foul odor.

  3. The More Active One of Arms the More Stinky the Armpit Can Be

  4. On average person, they do not use both arms at the same time. Which means that there is a possibility for one arm is more active than the other, indicating that when one arm is more active, there will be increased activity in the armpit that promotes sweat production and increased the population of bacteria causing underarm odor.

    If you are a right-handed, just like most of the population in the world, your right arm is certainly more dominant than the left one. Your right arm will be more active and produce more sweat, so the bacteria get more sweat molecules to feed and release more Organosulfur compounds called Thioalcohols which contain pungent odor.

    Some statistics also indicate that there are more right-handed than the left-handed people in the entire world population which will answer the common complaint of why the right armpit is smelly than the left one.

  5. Imbalance of Taking Care of One Armpit

  6. Providing a proper skin care including both your armpits is an elegant way to keep yourself away from body odor. It includes shaving and washing underarms and at the same time applying deodorant or antiperspirant that suits your skin type, and running these simple regimens will prevent your armpits from being smelly.

    However, for most people (maybe you too), they find it difficult to provide equal care for both sides of the armpit. It means that if the dominant part is your right arm, you tend to give more care to your left armpit rather than the other one. It results in your right armpit leaving more odor than the left one due to the lack of care and the other way around as well.

How to Get Rid of Underarms Odor Naturally

Now that you already know the three common reasons why only one armpit has more odor, you may also want to apply some simple tips to get rid of underarm odor in natural ways and keep your armpits to emanate good smell all day.

  1. Wearing Proper Clothes

  2. If you want to wear clothes, take the clothes made from breathable fabrics. It is imperative to allow the fresh air to flow unhindered inside and allow your body to stay cool. If your body stays cool, especially during the summer, the possibility of getting underarm odor is unlikely.

  3. Keep Both of Your Armpits Stay Clean

  4. Wash your armpits thoroughly; as it should be part of the body care that you need to run regularly. Use an anti-bacterial soap that suits your skin type. Most people take a bath at least twice a day, but they fail to devote their time to actually washing their armpits properly.

    Thus, the cleaner your armpits are, the less likely your armpits will develop the underarm odor, as the number of bacteria you have is getting smaller.

  5. Apply a Good Deodorant

  6. A good deodorant or antiperspirant in the armpit is of great help when it comes to facing underarm odor. Choosing a good deodorant can make a significant difference to your armpits in controlling bacterial growth. In addition, deodorant also provides extra fragrance for your body.

    A good deodorant means having safe ingredients for your body, and you can get them at a local store. Deodorant works in two different ways; the first is by increasing the acidic environment of your armpits, making it difficult for bacteria to grow. In addition, it also prevents your body from releasing more sweat which reduces the possibility of bacteria to ingest sweat molecules.

  7. Change Your Clothes on Regular Basis

  8. It is essential not to wear the same clothes for many times. The reason is that the clothes you have been wearing for a full day have increased the possibility for bacteria to grow. This condition is certainly not good for your body, especially since bacteria living in the clothing is responsible for the odor in your armpits as well.

  9. Reduce Spicy Foods Intake

  10. Consuming spicy foods can lead to the production of excessive sweating. So you should avoid or reduce your intake of spicy foods, especially when you have to attend certain important events. Reducing spicy food intake can put underarm odor under control at lovely moments in your life.

  11. Refreshing Up After Physical Activity

  12. Performing physical activity on a regular basis such as exercise can improve overall body health. Exercise can make your body more relaxed.

    However, you also need to give more attention for always refreshing up yourself once you have finished your exercise, which aims to reduce the possibility for bacteria to be more active in your body. The more you become lazy to freshen up, the more likely your armpits causing an offensive odor.

  13. Shaving Your Armpits

  14. Hair that grows under the armpits can trap the production of sweat in the armpits, allowing bacteria to swallow more sweat molecules and contribute to the underarm odor eventually. To overcome this problem, you are advised for always shave both of your armpits regularly if you want to avoid underarm odor.


You can apply some tips and efficient methods above to get rid of body odor the easy ways. Now you understand why only one armpit smells more than the other. And in most cases, body odor does not indicate any illness.

However, some cases of body odor also indicate a certain disease if you find your body odor occurs once you get certain diseases, and of course, it requires further investigation from the doctor.