Baking soda is well known for its ability to absorb odors. For instance, if you have a bad smell in your refrigerator, leaving an open box of baking soda in your fridge can help get rid of the odor.

This odor-absorbing ability has resulted in baking soda becoming a popular option as a natural deodorant.

Although studies have been done on the benefits of baking soda in general, there’s very little scientific research to specifically support its use as an underarm deodorant. The reported benefits are based on anecdotal evidence of people who have used it to combat their body odor.

One studyTrusted Source suggests that baking soda may have antimicrobial benefits, which could potentially mean that it has the ability to fight off odor-causing bacteria under your arms. However, this older study was done in the context of dentistry, and not skin care.

There may be other potential benefits of using baking soda instead of a conventional deodorant. This is especially the case for people who have a sensitivity to chemicals and ingredients used in many commercial deodorants, such as:

• Aluminum. Some people are concerned that absorbing aluminum from a deodorant can increase their risk of breast cancer and other cancers. However, there isn’t any scientific research to date to support this.
• Parabens. Although research is still ongoing, some early studies indicate that parabens found in beauty and personal care products may increase the risk of cancerous skin damage.
• Triclosan. This ingredient may disrupt some types of hormones.
• Artificial colors. These may cause skin irritation.

What are the drawbacks?

As a deodorant, baking soda may help neutralize odors. This benefit could come at a cost, though, especially if you have sensitive skin.

If you have dry or sensitive skin, you could be more prone to the following side effects if you use baking soda under your arms:

• redness
• rash
• itchiness
• scaly skin

The drying effect of baking soda is likely due to its alkalinity. A pH of 7.0 and above is considered alkaline, and baking soda falls somewhere around 9.0 on the pH scale.

According to researchTrusted Source, healthy skin is more acidic, at a pH of around 5.0. So, when you apply an alkaline substance like baking soda, it could upset your skin’s natural pH levels. This, in turn, could lead to excessive dryness.

One way to sidestep possible side effects is to test your skin’s sensitivity to baking soda before applying as a deodorant. This is called a patch test.

You can do a patch test by taking a small amount of baking soda and applying it to a small area of your skin, like the inside of your elbow. Then, wait for up to 48 hours to see if your skin develops any sort of reaction or irritation.

If you want to stay dry, you may have to reapply baking soda throughout the day. That’s because deodorants in general, including baking soda, only mask body odor, while antiperspirants work to prevent wetness by blocking your sweat pores.

How to make a DIY baking soda deodorant

To use baking soda as a deodorant, you can pat a small amount on your underarms. But this method can become quite messy and likely won’t work too well.

A better option is to make a deodorant paste by following these easy steps:

1. Mix about 1/4 tsp. baking soda with a small amount of lukewarm water in a bowl until it forms a paste.
2. Apply the paste to your underarms, gently patting it onto your skin with your fingertips.
3. Make sure the paste is completely dry before getting dressed.

You can also combine baking soda with other ingredients without using water.

• Mix 1 part baking soda with 6 parts cornstarch, which can act as an antiperspirant to keep you dry.
• Mix 1 part baking soda with 2 parts shea butter or coconut butter, which may be helpful for dry, sensitive skin.
• Mix 1 part baking soda with 4 parts coconut oil, and add a drop of an essential oil, like lavender or tea tree oil

No matter which recipe you choose, it’s important to conduct a patch test ahead of time to make sure your skin isn’t sensitive to any of the ingredients.

Alternatives

If baking soda causes your skin to dry out, itch, or become irritated, you may want to consider trying other natural deodorant options, such as:

• apple cider vinegar, diluted in water
• coconut oil
• cornstarch
• shea butter
• witch hazel
• tea tree oil or other essential oils diluted in a carrier oil

The bottom line

Due to its odor-fighting properties, baking soda may be able to combat underarm odor.

However, baking soda isn’t designed for the skin. It’s much more alkaline than your skin, which could disrupt your skin’s natural pH balance. This may lead to dryness, itching, redness, and irritation, especially if you have sensitive skin.

If you’re concerned about your current deodorant and want a more natural option, talk to your doctor or dermatologist about the best natural options for your skin.