Frequently overwashing your hair with shampoo can be another damaging factor to hair. From dry hair to hair loss, the negative effects of overwashing can get worse when combined with chemical treatments or dyes.
Disruption of Natural Hair Function
Human hair is typically more acidic than the scalp, so shampoos should usually fall within the same pH level, which is approximately 5.5. Shampoos with a more alkaline pH can lead to cuticle damage and fiber breakage.
Aggravating Hair Ailments
Shampoo can also exacerbate the following conditions:
Some scalps are sensitive to shampoos and their harsher ingredients, and this can result in dandruff, or in some more serious cases, contact dermatitis.
Your scalp needs its natural hair oils to moisturize and hydrate, but these oils are often stripped away from common shampoo ingredients such as sulfates.
Itchy and Irritated Scalp
An itchy scalp can be the result of not sufficiently rinsing shampoo, or in some cases, allergic contact dermatitis.
Ingredients like formaldehyde, dimethicone, and keratin, can possibly exacerbate hair loss, especially when used in high concentrations.
The Origins of Shampoo
Although it seems like an essential part of your shower routine, this wasn’t always the case when shampoo was first introduced to the public.
At the turn of the century, regularly washing your hair wasn't a common practice in many American homes. But with the advent of shampoo, images of thick, lustrous hair soon became the norm, as well as promises of cures for baldness, dandruff, and other follicle-related ailments. The demand for solutions to these problems rose, and the shampoo industry took root.
Ingredients and Innovation
Modern shampoo was invented about a century ago, and even at its inception, it was known to dry out and damage hair. Early shampoo was made from lard and lye, ingredients whose high pH levels resulted in split ends and dryness.
In the 1930s, the first man-made detergent was developed: sodium lauryl sulfate (SLS). Its ability to create lather in bathing products contributed to its popularity, and it was soon a common ingredient in shampoos.