How to Whiten Undershirts

man in v-neck undershirt
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So, you’ve gone to put on your once perfectly white undershirt, only to find that it has started to turn a grayish or yellow color? 

This unprecedented change in color has left you wondering what (if anything) you could have done to prevent this from happening in the first place and if your white undershirts will ever truly be white again. 

The good news is that not only can you prevent the color of your undershirts from changing, but there are some handy tricks to whiten your undershirts to as good as new again. 

Keep reading!

How Do Undershirts Become White In the First Place?

So, we can understand how to freshen undershirts back to their fresh white color, it’s important to note how they became that way in the first place. 

Your white undershirts, like every other piece of knitted clothing, start out as what’s called greige goods. 

Greige goods are loom state woven fabrics, or unprocessed knitted fabrics, meaning they are in their original state. 

From there, the greige goods may then be dyed, printed, and/or finished before they are converted into clothing.

To make your white undershirts as white as can be and away from the grayish greige goods color, the fabric mill will then use optical brighteners to bring the fabric to the desired shade of white.

How to Keep Undershirts White

in in white shirt

Before we talk about how to whiten undershirts that have already turned yellow or gray, let’s talk about something even more important – prevention. 

We all know that preventing a problem from occurring in the first place is much more useful than having to go ahead and fix the damage afterward. And there are plenty of solutions available to keep your undershirts white. 

Let’s take a look at some of the easiest ways to avoid off-color undershirts.

Separate Your White/Colored Wash Loads

Making sure that you separate your white and colored wash loads from each other is one of the easiest and most effective ways to keep your white undershirts white. 

When you wash your white undershirts with other non-white clothing, the colored dye can run into your pure whites, causing them to not only potentially become gray but any other color under the rainbow (ever accidentally washed a red sock in with a load of whites and got a dryer full of pink clothes?). 

Of course, you may be wondering what to do with those items of clothing that are mostly white but have a small area of color here and there. 

Can they be washed with your white undershirts, or do you have to put them in their own separate load? 

Thankfully some products can help with that if you’re unsure but would rather avoid an entirely separate wash. Try Haggin Family Company’s Color Keeper or the Shout Color Catcher Sheets for Laundry to catch loose dye in the wash before it clings to your pure whites.

Separate Super Soiled Clothes 

You may quickly be noticing a pattern here that separation is often key to keeping your undershirts white. 

If some of your whites are particularly dirty and grimy from work, then you’re definitely going to want to keep them separate from your less soiled undershirts. 

This is due to the fact that dirt can actually transfer in the wash, graying or yellowing everything that surrounds it. 

If you don’t want to split the loads, consider pre-soaking your heavily soiled whites in a stain remover before washing them.

Do Not Overload Your Washing Machine

Oddly enough, putting too much in your washing machine can even affect the color of your white clothing. This is because overloading your washing machine prevents your clothing from moving freely in your washing machine, so dirt cannot be removed as effectively. 

What’s considered overloading? Don’t add any more clothes after the drum is three-quarters full. 

Follow the Dosage Instructions On Your Detergent

Did you know that not following the dosage instructions on your detergent can mess with the color of your clothing? 

By using too little detergent, you may not be cleaning your clothes effectively, and by using too much, you could not only be affecting how your shirts look but causing your clothes to carry an odor and even wear down the machine.

How to Get Undershirts White Again

Now, let’s talk about how to get undershirts white again after they’ve turned that less than desirable grayish color or have developed those embarrassing yellow pit stains. 

While the graying of your shirts is generally caused by any combination of the incidents we spoke of above, yellow stains are slightly different. 

Yellowish stains are caused by a mixture of sweat and antiperspirant or deodorant and are primarily triggered by the aluminum found in these products. 

So, while the preventative measures that we spoke about are all very well and good, you’re probably here to find out how to whiten your undershirts after that graying or yellowing has already occurred. Let’s take a look at what your options are.

Fabric Stain Removers

Fabric stain removers are no joke when it comes to removing yellow or gray stains from your white clothes. 

In particular, the Vanish Fabric Stain Remover for Whiter Whites has been known to work wonders on your discolored clothing. 

This super-boosted formula removes body marks, as well as dried-on dirt and grime, and will bring your whites as close to their original color as they will get. 

Throw a scoopful of this amazing stuff in with your white undershirts every time as a preventative measure or pre-soak your already stained clothing before throwing it into the wash with some Vanish once again.

Creating Your Own Stain Remover Mixture

Generally, searching for a stain remover containing hydrogen peroxide and baking soda will be your most effective option for a stain remover. 

However, not all stain removers are created equal, which is why creating your own is sometimes best. In this case, you’ll be able to know exactly how many of these ingredients are contained in your stain removing concoction, rendering them more effective than most on the market.

When it comes to removing yellow stains, pretreating your undershirts is always better than just throwing them right in the washer and expecting a miracle. 

Instead, consider pre-soaking your undershirts using the following concoctions before putting them in the washing machine to get the most out of these super effective ingredients. 

It should also be noted that the longer your shirt is allowed to soak in hydrogen peroxide, the better, so don’t be afraid to soak your white undershirt overnight to get out those super tough yellow stains.

Dish Soap, Hydrogen Peroxide, and Baking Soda

Baking so for shirt cleaning

You’ve probably heard of using dish soap to get rid of tough stains, as it can basically get rid of anything.

 We’re talking wine, grease, sauce, and even blood. This is because it can effectively break down oils and grease, making it a fantastic pretreatment for any type of stain. 

By combining dish soap with hydrogen peroxide, you’re looking at a force to be reckoned with for those dingy yellow stains.

Here’s how to use it:

Combine 1 cup of dish soap with 2 cups of hydrogen peroxide and pour generously over any yellow staining on your undershirt. Let your shirt sit for a minimum of one hour before taking a toothbrush or sponge and rubbing dry baking soda over top. 

From here, you can throw your undershirt(s) into the washer on cold (do not use hot or you risk setting the stain into the fabric). 

Any yellow stains should be removed after one cycle, but don’t be alarmed if it doesn’t work the first time on older stains. You may need to repeat the cycle another time or two to completely get rid of them.

Hydrogen Peroxide, Baking Soda, and Salt

Salt is another one of those fantastic natural ingredients that can absorb grease and oil, making it similar to baking soda. This is another abrasive substance that can create a saline solution once it comes into contact with water, which can break down protein-based stains. 

By mixing it together with baking soda and hydrogen peroxide, your stains are facing a force to be reckoned with.

Here’s how to use it:

Mix 1 ½ cups baking soda, 2 tsp hydrogen peroxide, and 1 ½ tsp of salt. Pour the mixture on your yellow stains and allow to sit for at least 30 minutes. 

After it’s had time to set, take a toothbrush or a sponge and lightly scrub the stained areas of the undershirt. From here, your shirt is ready to toss in the laundry machine on cold to hopefully relieve those stubborn yellow stains.

How to Keep White Undershirts White

We hope we’ve given you some great ideas on how to keep your white undershirts white and how to lift those stubborn yellow stains if they just couldn’t be prevented. 

While you may be tempted to simply throw your undershirts into the wash after drowning them in Chlorine bleach, try to avoid doing that. 

Bleach can actually make the yellowing worse depending on the fabric and can permanently set it in. 

Plus, it’s guaranteed to wear down the fabric of your undershirts and is not ideal for sensitive skin. We wish you the best of luck in your mission to bring your undershirts back to their brand new white!

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