baking soda and hair

September 12, 2007 9:45 AM

What is baking soda doing to my hair?

I've been using baking soda (mixed with water or baby shampoo to make a paste) to wash my hair for the past couple of months because it cleans my oily hair better than any shampoo I have come across.

Since then, my (dark brown) hair is noticeably lighter. After coming back to school a number of people have commented on it.

Is the baking soda really bleaching my hair over time? Will my hair continue to get lighter and lighter as long as I continue to use it? I don't mind the slight difference now, but I don't really want my hair to get significantly lighter. This also makes me question whether it is safe for me to be slathering baking soda paste all over my head every other day or so.

posted by puffin to Health & Fitness (9 answers total)

I don't remember the exact source now, but I think baking soda can, in fact, lighten your hair. I read about it one while poking around on a message board for the "no poo" lifestyle. It's a thing where people with dry or curly hair don't use shampoo and instead scrub their scalps with conditioner. To help get the scalp clean without stripping oils from the hair, many people also scrub with baking soda because it's abrasive. A number of people there mentioned the lightening effect.
posted by mostlymartha at 10:10 AM on September 12, 2007

According to this site, it will lighten your hair but you can use rosemary to darken it again. You might be able to find other useful information there, or on other "poo-free" pages.

"Rosemary: tonic and conditioner, one of the best herbs to use, gives luster and body, also slightly darkens the hair. (This is good to use if you notice your hair lightening due to baking soda use.)"
posted by knapah at 11:17 AM on September 12, 2007

I use baking soda too, but only a pinch mixed into the shampoo every few days when I feel that I have buildup. I haven't noticed any lightening.

By the way, you can learn more than you ever wanted to know about hair care at the Long Hair Community.
posted by happyturtle at 12:05 PM on September 12, 2007

As I recall, somebody in an Ask MetaFilter frugality thread mentioned that they used baking soda as a shampoo and that they had to follow up with vinegar to fix the Ph change that baking soda brings.

I don't know if I'm remembering that right or if the original poster was correct or not.
posted by willnot at 1:26 PM on September 12, 2007

Baking soda is definitely a mild bleaching agent. If you don't correct for it, your hair will continue to lighten.
posted by Malor at 1:54 PM on September 12, 2007

Best answer: Baking soda and water is a mild base (alkaline). Bases degrade proteins, and that's why it's bleaching your hair. Bases also saponify oils, making them water-soluble. That's why it works so well on the oil on your hair.
http://www.newton.dep.anl.gov/askasci/chem03/chem03753.htm
http://en.wikipedia.org/wiki/Baking_soda

Safety wise, this isn't drain cleaner we're talking about however. It's not going to do anything besides bleach your hair a bit.
posted by sebastienbailard at 5:47 PM on September 12, 2007

Response by poster: sebastienbailard: Thanks, that was the answer I was looking for. It sounds like I'll either have to accept the bleaching effect along with the excellent cleaning power of baking soda or just use it less often...
posted by puffin at 7:28 PM on September 12, 2007

(I may actually be wrong about the mechanism by which the baking soda bleaches your hair, that was just the result of a bit of googling.)
posted by sebastienbailard at 8:19 PM on September 12, 2007

If you are looking for an alternative to the baking soda you might want to try this shampoo from Redken. I use it when my hair gets really oily and it works pretty well.
posted by whoaali at 12:25 PM on September 13, 2007