Baking soda helps relax hair naturally but does not completely straighten it. It makes curls looser and softer, helps clarify the hair by removing impurities, which can make hair sleeker and shinier. Baking soda is gentler and safer than many commercial hair relaxing or texturizing treatments, though it can damage the hair or irritate the scalp if used incorrectly.
Wash your hair with shampoo, following your normal hair washing regimen. Towel dry until your hair is about 80 percent dry. If your hair is not dry enough, it will be difficult getting the baking soda mixture to remain on your scalp.
Mix the baking soda and conditioner together. You can add nourishing oil, such as avocado, coconut, or grapeseed, to this mixture or add it to the deep conditioning treatment later. The exact ratio of baking soda to conditioner will vary according to hair type and scalp sensitivity. Use less baking soda to play it safe. The consistency should be thick and creamy.
Apply the baking soda and conditioner mixture to your hair, working from root to tip. Do not rub the mixture in because it may irritate the scalp.
Put a shower cap on, covering all your hair. You can also wrap a hot towel over the shower cap. To prevent the mixture from dripping out of the shower cap, tuck a hand towel, paper towels or a scarf into the edge of the cap.
Leave the shower cap on for at least half an hour. It may be left on for many hours, but not overnight. This step will take some experimentation before you find the perfect treatment time for your hair needs. End the treatment if you feel any pain or burning.
Rinse your hair thoroughly with cold water but do not detangle it at this point. Deep condition your hair immediately. If you did not add the nourishing oil to the baking soda and conditioner mixture before, add it to your deep conditioning treatment now. Leave this treatment on for at least an hour. The longer you left the baking soda on, the longer you should deep condition.
Detangle your hair with the deep conditioner in. Work any tangles out gently with a wide-tooth comb. Rinse your hair thoroughly and style it.
If you use less than 1/4 cup baking soda, mix it with 1/2 cup conditioner or the baking soda mixture will be too dilute to be effective.
After applying the baking soda mixture to the hair, you may rub the scalp gently to exfoliate. Be careful not to overdo it and stop if it feels uncomfortable.
Hair type and scalp sensitivity vary, so note your results to perfect the process for your own hair.
Baking soda is very alkaline compared with the natural pH of hair, so using too much baking soda or leaving the mixture on for too long can irritate the scalp and damage the hair.
Do not perform this treatment more than once a month.
Niki Foster has been writing since 2005, with her work appearing on various websites. She earned her Bachelor of Arts in linguistics and anthropology from the University of California-Los Angeles and is working on her doctorate in linguistics at the same school.