Hair can become dry and unmanageable due to a poor diet, your oil glands, the weather or contact with harmful elements, such as the chlorine in your swimming pool. The dryness can make the hair dull and lifeless-looking. Citric acid is a component in many hair shampoos due to its benefits, but that doesn’t mean it is necessarily good for your dry hair.
Citric acid found in your shampoo products has two purposes: to act as a buffer with the other shampoo ingredients — balancing the pH level — and to remove soap scum from your locks. The effect of citric acid on dry hair can be counterproductive, since it is strong enough to strip the hair of soap scum. As citric acid strips your hair of scum residue buildup, it also strips it of other things, including moisture.
Although citric acid will strip your dry hair of its moisture content, the shampoo containing it will at least give your hair a very nice shine. As dirt and grime are removed from your locks, as well as soap scum buildup from some shampoos, your hair cuticle and follicles flatten, making your hair look shinier and more lively in color.
Lemon citric acid is sometimes used as a natural highlighter for blondes; it is applied prior to activities in the sun, which intensifies the lightening effect of citric acid. According to Roger Clemens, a molecular pharmacology and toxicology professor at the University of Southern California, it is the combination of the acid in lemons, the sun’s UV rays and oxygen that causes this acid oxidation hair coloring effect. Dry hair absorbs moisture anywhere it can get it, so if you apply citric acid to your hair via lemon juice, it will soak it up. However, sitting under a beauty hair dryer or out in the sun to get the citric acid to heat up will also dry your hair out even more. Moisturize your hair heavily if you decide to lighten your hair this way.
Don’t discard your lemons just because they can dry your hair out. Create a homemade product using lemons and moisturizing ingredients, such as mayonnaise and olive oil, and you can counteract the negative effects of citric acid on dry hair while you enjoy the positive benefits of shine and and a lighter color without having to pay your hairdresser.
References and ResourcesAPAC Chemical Corporation: Citric Acid - Hair Shampoos and Rinses
Exploratorium: Better Hair Through Chemistry
The New York TImes: Hair-Color Recipe: A Dash of Sun, A Pinch of Lemon
Olive Oil Detox: Lemon Moisturizing Hair Treatment