Internet is a never-ending source of trends and fashions, some of which may be harmful for our skin and hair. The latest fashion is ‘no poo', that is, not to use shampoo for your hair but to wash it instead with water, baking soda, vinegar or other substances. Dermatologists warn of the risk that these practices may lead to skin infections.
Recent years have seen the spread of a new, supposedly ‘eco’, fashion that advocates replacing commercial shampoos, which contain artificial ingredients and chemical additives, with ‘no poo’, supposedly a more ‘natural’ method of washing the hair. In English, the pun on ‘poo’ reinforces the idea that the shampoos available in the market are not free from objectionable matter. This scalp care method has a few variants.
The simplest variant is to wash your hair with spring water, as our ancestors might have sporadically done when they crossed a stream. Advocates say that, although your hair gets greasy in the first few weeks, its appearance subsequently improves greatly because sebum production eventually regulates itself.
The acid-alkaline bomb
The most widely used method is to dissolve baking soda in water and rub the hair and scalp with the mixture. If you have greasy hair, that should be sufficient, as the bicarbonate removes the sebum. However, if you have dry hair, the ‘no poo’ method recommends using apple cider vinegar as a conditioner.
So ... let’s see: baking soda is alkaline, with a pH close to 8, whereas vinegar, containing acetic acid, has a pH of 3. So, first attack the skin with a very basic element, and then finish off with an acid?
The opinion of experts
What do dermatologists think about ‘no poo’? The Spanish Academy of Dermatology and Venereology (AEDV) has this to say:
"... shampoo removes the oil produced by the sebaceous glands that traps dead scalp cells, dirt and other substances we apply, such as sprays, gels, etc. This oil or sebum must be removed periodically for reasons other than the merely aesthetic, as it is an important source of microorganisms that could induce infections.”
Doctors also warn of the effects of baking soda, as overuse has a rebound effect and the skin ends up producing more oil. Also, its high alkalinity can cause irritation and can even bleach hair.
So, don’t pay any attention to false myths about what’s ‘natural’. All the experts advise against the ‘no poo’ method and recommend using alcohol- and fragrance-free shampoos. Best choose gentle – that is, neutral – shampoos, preferably those with a pH between 4.7 and 5.5.