Whether or not you wear an undershirt comes down to your comfort preferences. Some people hate the feeling of an extra layer of clothing under their shirt while for others, an undershirt is a lifesaver, keeping them warm, comfy and sweat-free. 

If you are not sure whether or not you should wear an undershirt, we discuss the pros and cons of undershirts in this post. 

What are Undershirts For? 

To start, let’s talk about why the heck undershirts exist. To be clear, it’s not for fashion. 

You can wear a regular tee under your shirt to create a casual style, but that’s not an undershirt. A proper undershirt is typically not visible from under your outer shirt. Undershirts are thin and have a deep plunging neckline that’s not visible even when you’ve opened a couple of buttons on your shirt. 

Undershirts are all about comfort, rather than aesthetics. You can think of an undershirt as a second skin, providing extra warmth, sweat absorption, a soft texture and other benefits.

While undershirts are typically worn with dress shirts, you can wear them under any kind of shirt including a polo, Henley shirt, and even a regular t-shirt.  

6 Reasons to Wear an Undershirt 

1. Sweat Wicking and Preventing Sweat Patches

Undershirts are great for sweat control. If you sweat a lot from your pits, back or any other part of your upper body, a good undershirt will wick or absorb sweat from your skin. 

This has two big advantages. One, the undershirt keeps your skin dry, ensuring you stay comfortable, reducing odors and preventing sweat acne. 

Two, an undershirt prevents sweat patches from showing on your outer shirt. If you are an extra-heavy sweater, you can get a sweat-proof undershirt such as Thompson Tee that blocks sweat from reaching your outer shirt. 

An undershirt can also protect your shirts from pit stains. 

2. Less Body Odor 

By absorbing or wicking away sweat, an undershirt keeps it from pooling on your skin. Along with a good deodorant or antiperspirant, an undershirt reduces or prevents body odor. 

For extra protection against body odor, wear an undershirt made from natural fibers like cotton, linen, silk or bamboo. Natural fabrics are more resistant to odors since they don't attract the kind of bacteria that stink up your clothes. 

For even stronger protection, get the Hercleon antibacterial undershirt. It’s made with special fibers that fight off odor-causing bacteria, keeping you smelling fresh no matter how hot and sweaty you get.  

3. Extra Warmth 

Undershirts are a great way to layer up when the weather gets chilly. And because most undershirts are lightweight and breathable, you don't have to worry about overheating. 

For extra-chilly weather or if you are going outdoors, look for a thermal undershirt. Thermal undershirts are designed specifically to retain warmth. They are typically synthetic, made from materials like polyester, spandex and fleece. Natural merino wool undershirts are also excellent for cold weather.  

4. Prevents Chafing and Irritation 

If you have sensitive skin that chafes easily or gets irritated by certain fabrics, an undershirt can help. Because undershirts are meant to fit snugly against the skin, they are designed to be extra soft and skin-friendly. They provide a protective barrier against rough outerwear. 

5. A slimmer Profile

We mentioned that undershirts are not for aesthetics…usually. Some undershirts can make you look trimmer and better. 

A compression undershirt is a type of extra-snug undershirt that can give you a slimmer profile. It works by reducing the appearance of folds and bulges under your clothes. It can help you reduce the appearance of your belly or man boobs. 

6. Extra Support During Exercise

You can also get a compression undershirt to provide extra support to your muscles and increase blood flow when you are working out. It works the same way as compression sleeves or socks. 

Potential Downsides of Wearing an Undershirt 

• Some people just don't like how it feels. 
• If you sweat a lot, a cotton undershirt will stay damp and can feel uncomfortable. Wear a synthetic, linen or bamboo undershirt instead. 
• Synthetic undershirts are great at wicking away moisture and staying dry, but they are less odor resistant. If you are prone to BO, wear a natural or antibacterial undershirt instead. 
• Some undershirts, particularly synthetic ones, can end up making you too hot on a warm day.  

Final Thoughts

If you decide to get an undershirt, make sure you buy the right one. Here’s a quick guide we wrote on how to shop for a good undershirt for men. It goes into specifics like fabric, fit and style.