Sweat-Absorbing Undershirt – The Rescue Under Your Shirt
Short answer: A sweat absorbing vest takes up sweat before it reaches the shirt, and that is the only method against visible marks under the arms that does not involve changing shirt. Bamboo viscose absorbs moisture into the fibre and feels dry for longer than cotton.
Where the marks come from
Sweat becomes visible once it reaches the outside of the shirt. With nothing in between, that happens within minutes in a warm room. A layer that absorbs the moisture first moves the problem away from the fabric other people can see, and that is the whole mechanism.
Sleeves are what matter
A sleeveless vest does not cover the place where the marks appear. If it is to make a difference under the arms, the fabric has to reach past the armhole. That is the single detail that decides whether the vest solves the problem or merely feels pleasant.
The material has to hold moisture
Cotton soaks it up and turns wet and heavy, and then the moisture reaches the shirt anyway. Bamboo viscose absorbs moisture into the fibre itself and releases it slowly into the air, so it lasts longer before it is saturated. Have a look at the bamboo vests for men.
The fit decides the rest
The vest has to touch the skin all the way round. If it sits loose under the arm there is air in between, and the sweat reaches the shirt past the fabric. Take the smaller of two sizes as long as it does not pull across the shoulders, and make sure it is long enough to stay down.
Colour under a pale shirt
Under a white shirt a white vest shows more clearly than a nude one, because white fabric throws the light back. Under navy and black the colour can be anything. Two vests, one in each colour, therefore cover the whole shirt cupboard.
For the genuinely long days
If the day is long and the room is warm, a change does more than any fabric. Put a clean vest in your bag and change halfway through. It takes two minutes and is the only method that resets the day to where it started.
The same goes for women
Under a thin blouse a bamboo vest for women solves the same problem, and there it is often sleeves or a wide strap that decide whether the fabric covers where it should. The rest of the range sits under bamboo underwear for men.
Washing does not remove everything
Sweat left in the fabric for a day sets as odour in the fibres, and it gets harder to remove each time. Wash the vest the same day at 30 degrees without fabric softener, and skip the tumble dryer so the fabric keeps its ability to move moisture. See also bamboo and temperature regulation and washing guide for bamboo clothing.
Frequently asked questions
Does a vest help against sweat marks?
Yes, if it has sleeves and sits close. Without sleeves it does not cover where the marks appear, and then it makes no difference to the outside of the shirt.
Does one more layer not make you warmer?
No, if it is thin and breathable. Dry skin feels cooler than damp skin, and it is the moisture between skin and fabric that creates the warm, clammy feeling.
Can sweat marks be washed out of a shirt?
Old marks with dissolved deodorant are hard to remove completely. It is easier to prevent them with a layer in between than to treat the shirt afterwards.
See our range of women's bamboo undershirts.
