Dyson has been researching the science of style for more than a decade, investing £100m into its hair laboratories globally, and delving into the science of colour fade. This has helped uncover insights that reveal how, with the right education and hair tools, damage and colour fade can be controlled.
Four reasons for hair colour fade
There are many reasons why hair colour can fade, which includes the type of colourant used, the chosen colour, washing frequency, UV exposure, cuticle damage and the use of high temperatures for styling.
Here we explore some of these in more detail.
Overexposure to sun can cause hair damage. Bright sunlight can erode the vibrancy of hair colour by destroying its natural melanin pigments while dye molecules can also escape more easily from damaged hair. Overexposure can also damage the keratin in hair, so it feels brittle.
UV has been shown to degrade the colour molecules formed during the dyeing process. This degrading process causes the colour to fade, impacting overall look and shine. Wearing a beach hat or staying in the shade is a simple way to limit UV exposure. In natural hair, UV light and temperatures above 81∘C can cause unpigmented hair such as white or grey hair to turn yellow. This change is more visible in unpigmented hair as the existence of melanin in pigmented hair will mask the change and may slow the reaction.
Chlorine in swimming pools can cause the hair cuticle to become damaged, increasing strand friction and the impact of mechanical damage. Copper algaecides are sometimes used to help keep swimming pools clear of algae. Those with bleached hair should take note that the copper algaecides have been shown to cause bleached hair to turn slightly green. Washing hair as soon as possible after a swim with a mild shampoo helps minimise the risk of damage.
Sea and sand
Sea water leaves hair coated in a layer of salt which increases the friction of the strands and causes damage that can lead to breakage. While salt from the sea will not cause significant chemical damage, it can dry it out slightly. Sand is an abrasive material that can wear down the cuticle layers. To avoid this, gently wash salt and sand out of hair as soon as possible.