Hair dyes are currently an option that can be used by women and men to renew or improve their appearance and style. However, the use of these products, which are mostly composed of chemicals, still raise some doubts. Above all, due to the lack of knowledge of the long-term effects that they could have on the health of its users.
This has generated a grey area in which some myths have emerged, which over time have become established as truths. Therefore, below, we will analyse the main ones and finally reveal which are true and which are not.
All hair dyes are the same
False Since, there are three types of colouring, which differ in the duration of the colour, which will depend on the composition of the dye. This is what we will have:
Temporary hair dyes
Due to their large pigment molecules, they only add colour to the outer part of the hair, by adhering to it. Which allows them to be removed by washing.
Semi-permanent hair dyes
They are dyes that due to their smaller molecules can penetrate the capillary cavities, slightly altering their structure. This without the need for discolouration, also does not contain peroxide or ammonia, or in very low quantities. They generally last between 4 and 5 washes.
Permanent hair dyes
These have such tiny pigment molecules that they can fully penetrate the hair shaft and remove the natural pigment from the hair. Thanks to the fact that they contain ammonia and hydrogen peroxide, which make it easier to bleach the hair and make the colour set permanently.
When the root grows with the original colour, it is necessary to reapply, and equally to get rid of it requires bleaching again.
Blond hair dyes hide grey hair better
True in general, this hair tone makes grey hair dissimulate better. Making the contrast between the roots and the rest of the hair not look so marked. In contrast, darker hair tones show much more growth and the appearance of grey hair. So they will also need colour touch-ups more frequently.
Dirty hair is best dyed
True Since if it is freshly washed, the hair fibre will be unprotected, which can cause irritations and the dye does not set well. On the other hand, being dirty the natural oils of the hair will help protect it from allergies and irritations. Also making the colour pigments adhere better to the hair fibre. Therefore, if you are going to dye your hair, it is best not to wash it.
Excessive use of dyes causes hair loss
False Currently there is no evidence of the relationship between hair loss and the use of dyes. What can cause the excessive use of dyes is that the hair fibre is weakened, especially by those hair dyes that involve discolouration. Well, they alter the physicochemical properties of the hair, making it weaker and more brittle. Causing volume to be lost, but not to fall from the root.
Hair should not be dyed during pregnancy
False Although the concern about the presence of chemicals such as ammonia and hydrogen peroxide is understandable. There is no conclusive evidence or sufficient study to suggest that hair dyeing can harm the foetus. But if the manufacturer’s instructions are followed and the exposure times are respected, the risk is minimal.
What happens is that the dye is not in contact with the skin long enough for it to be absorbed into the bloodstream. Therefore, it is difficult for it to represent a danger to the foetus. What can mean a problem is that an allergic reaction or irritation occurs when the product comes into contact with the skin.
Although this is normal with the application of these types of products, whether you are pregnant or not. But in any case, it is advisableto avoid its use if the person has doubts.
Anti-dandruff shampoo removes colour from dyes
True This type of shampoo is composed of different active ingredients that have greater drag power. Among them the sulphites, zinc and selenium sulphide present in most of the anti-dandruff that exist. Therefore, they not only remove the dandruff particles present on the scalp, but also accelerate the loss of colour.
It is therefore advisable that we avoid them if you have dyed hair. But if you want to preserve the colour and at the same time keep dandruff under control. What the experts recommend is that you alternate the use of anti-dandruff shampoo with another that allows you to maintain the pigment.
Hair should not be dyed during menstruation
False Although during this period of time women have greater sensitivity and low defences, the dyes do not have a greater effect due to having menstruation.
However, there are times when you should avoid colouring your hair. For example, if we have an allergy to the dye or any of its components, if we experience hair loss processes, or if we are going through inflammatory processes of the scalp such as psoriasis or seborrheic dermatitis.
Semi-permanent dyes are better than permanent ones
False Although these have different compositions and the results also differ. In the long term it is less damaging for the hair to use permanent dyes. The reason for this is that the hair only needs to touch up the roots as they grow, to avoid colour differences. Whereas with temporary dyes the hair must be dyed over and over again.
No product lengthens the colour for longer
False There are a large number of products formulated to provide hair with the nutrients and care it needs to protect it from the aggressions that discolouration can cause. Therefore, keeping it healthy, without split ends and with a closed hair fibre, it is difficult for the colour to fade, making it last longer.
Natural dyes are just as good
False Although its use supposes greater benefits for the hair and does not damage it at all, the results are not the same. Since natural dyes do not have the same colouring power as ammonia hair dyes.
However, they are ideal for enhancing natural hair colour, adding highlights, or slightly changing the colour. All this without the drawbacks of permanent dyes, such as the so-called root effect.
ALFA