Updated on July 7th, 2023 at 07:43 pm

When looking in the mirror many women wonder whether what they’re seeing is armpit fat or just axillary breast tissue. Both of these show themselves as excess folds of skin and tissue around their armpit area. Which is different from extra fat being stored in the breasts or even Gynecomastia vs fat.

image of axillary breast tissue vs armpit fat - Extra Large Living

This is something that can affect people no matter their weight, age, or size. The majority of the time the issue is actually armpit fat. Despite the fact that it can make people feel quite insecure, it is very normal.

Sometimes, the problem may be axillary breast tissue. This is where things become a little more complicated and problematic.

Because of this, it is important to understand the differences between the two as well as how to tell the difference for yourself. We will explore what armpit fat and axillary breast tissue is, as well as how it comes about.


What is armpit fat? 

No matter your age, size, weight, or gender, you can have armpit fat. The majority of the time it is women who suffer from it. A lot of this can be explained by tops and bras being particularly tight in the underarm area which can result in a fatty look in the armpit area due to skin spilling out over the undergarment. But the biggest factor is genetics. 

Your genetic makeup can entirely affect the way that your body stores fat. If you have noticed that your family members also have armpit fat, then you’ll probably suffer from it too. On top of that, people who are overweight and carrying excess fat will also find themselves with armpit fat.

It is important to note that tight-fitting tops and bras do not cause armpit fat. They accentuate the appearance of fatty armpits.  Armpit fat could worsen over time, especially if you gained weight during the pandemic.

Causes of armpit fat

You can find armpit fat on anyone, however, it does seem to be more profound in women than men. The types of clothing that you wear can affect the way that your armpit fat appears. However, this isn’t the only cause for armpit fat being present in the body. Other causes include:


This is the biggest factor when it comes to developing armpit fat. The way your body distributes fat is entirely dependent upon your genetic makeup.


People who are overweight may experience more fatty deposits in their armpit areas. This is also still affected by your genetic makeup. If you gain weight, then you may start to notice more fatty deposits appearing in your armpit area. This can be reduced by partaking in a nutritious diet as well as some additional movement into your everyday life. You can’t spot reduce fat, but it should help to alleviate the overall appearance.


When your body produces more hormones such as estrogen and progesterone, you will start to notice that your breasts swell. This can be during pregnancy, menopause, menstruation, or even puberty. Hormonal changes such as these will increase the way that your skin appears and stores fat in specific areas, such as the armpit.

image of axillary breast tissue vs armpit fat - Extra Large Living


Believe it or not, poor posture can also affect armpit fat. It may not be the root cause of its development, but it can make it look more prominent.

If your shoulders are rolled forward in a poor postural position, potentially creating what many call a buffalo hump, then standing or sitting up straight may help to reduce the appearance of any underarm and armpit fat. Check out this article to find out: If lose weight will my buffalo hump go away?

Axillary breast tissue

Axillary breast tissue is often confused with armpit fat due to the fact that it looks so similar, and this is where the confusion comes in. However, they are two different things.

Axillary breast tissue isn’t composed of fat, it is composed of breast tissue that isn’t in the usual breast area. This tissue finds itself in the armpit area, also known as the axilla. Axillary breast tissue is still fibrous and exactly like breast tissue that you would normally find in your breast area. This type of tissue isn’t detrimental to your health, but it can prove to be an insecurity when it comes to people’s appearance.

This type of tissue tends to respond to varying hormone levels. As a fluctuation in a woman’s cycle happens, her hormone levels fluctuate with it. This happens during pregnancy, menopause, puberty, and even their menstrual cycle month to month. So, you may actually be someone who has axillary breast tissue rather than armpit fat.

Can exercise reduce it? 

For anyone that is overweight, you can try exercising to reduce the appearance of any fatty tissues that may be in your armpit. Exercise can also be useful to help reduce the appearance of axillary breast tissue.

For some people, when they lose weight, they may find that their breasts also reduce in size. This means that it is entirely possible to reduce the size of axillary breast tissue. However, it is unlikely to entirely disappear.

It is also important to note that it’s not possible to spot reduce fat. This means that you may lose weight in other areas but not your armpit area. This applies to both axillary breast tissue as well as regular armpit fat.


Another option for those who feel like they may need it is to reduce the fatty deposits through weight loss with liposuction. There are plenty of surgeries that will be able to offer this service. However, it is best to have a detailed consultation with the surgeon before you go ahead with any procedures as they may be able to offer you alternative solutions.


Axillary breast tissue won’t cause any health complications, but it can be something that makes you feel quite insecure.

Understanding whether you have this extra breast tissue or whether you have armpit fat can help you understand ways to reduce the appearance of it in the long run. For more information be sure to check out the rest of Extra Large Living!