Many women who suffer from hair loss, bald patches, and thin, brittle hair use products to help their hair to look its best - whether this means dyeing, straightening, or bleaching the hair - but this can cause or exacerbate hair loss. Keep reading to learn how and why some of the most popularly used hair products are, unfortunately, also the most harmful to hair.
While most dyes contain moisturizing compounds and come with conditioners to limit hair damage, repeated use of hair dyes can lead to hair loss. Lead, a key ingredient in most hair dyes, has negative effects on the central nervous system; the oxidative stress applied to the the scalp is likely to contribute to hair loss.
Bleach is a harsh and extreme way of dying the hair by removing its original pigments. Since bleach contains peroxide and ammonia, bleaching is damaging to hair even with responsible use, as it reduces moisture in hair shafts, often leading to dry, brittle hair and subsequent thinness. Bleaching should be done by professional hairdressers to limit damage and monitor the process, since improper application may cause hair to break off at the root.
Using heat-based styling products is also harmful to the hair. Curling irons, straightening irons, and even hairdryers cause surface damage to the hair shafts, making dryness, breakages, and thinness more likely. While using hair products from time to time is unlikely to have a significant impact on hair health, regular or heavy use is likely to cause or contribute to hair loss.
Henna is a plant compound that's used to add a reddish-brown tint to the hair. Though it's natural, henna can cause irritation and reaction in the scalp, particularly if left on for too long or applied to sensitive skin. Scalp irritation and resultant hair loss can also happen if henna isn't thoroughly rinsed after application. To ensure all henna is washed from the scalp after application, rinsing should continue until the water runs clear.
Hair relaxers use chemicals to loosen curls in curly or frizzy hair to straighten it. Relaxers contain a number of potentially harmful chemicals, including lye, which often causes scalp irritation, burning, and may lead to hair loss.
To prevent hair loss, limiting the amount of hair products you use can be helpful. However, if you do use products every so often, be sure to do a patch test first; rub a small patch of dye on your elbow or behind your ear - if no signs of irritation appear in 48 hours, the product is probably safe to use. Follow the instructions on the packet carefully, and be sure to balance harmful product use with healthy ones, like nourishing moisturizers and hair masks
- Environmental Protection Agency. (2012). Healthy hair care and the environment. Retrieved June 9, 2014, from http://www.epa.gov/region9/healthy-hair/health.html
- Food and Drug Administration. (2014). Hair Dyes and Relaxers. Retrieved June 9, 2014, from http://www.fda.gov/forconsumers/byaudience/forwomen/ucm118527.htm
- Lee, Y. et al. (2011). Hair shaft drying from heat and drying time of the hair dryer. Annals of Dermatology, 23(4), 455-462. doi: 10.5021/ad.2011.23.4.455
- Office on Women's Health. (2008). Skin and Hair Health. Retrieved June 9, 2014, from http://www.womenshealth.gov/publications/our-publications/the-healthy-woman/skin_hair.pdf