UV rays: why are they harmful for my hair?

What with pretty highlights and the 'straw effect' the sun can give our locks, it is difficult to know what the sun is really doing to our hair. We take a closer look at the harmful effects of UV rays.

UV rays damage the hair's keratin...

The sun can be good for your hair, as Vitamin D from sunlight boosts the production of keratin (an essential protein). However, when your hair is overexposed, it has the opposite effect. With continued exposure, the UV rays lift the hair's cuticles and thus weaken the hydrolipidic film protecting them, as holes are formed. The result: a loss of keratin and the hair fibre becomes drier and thinned out. Your locks also feel coarse , look dull and become prone to breakage. The sun damages the internal structure of the hair, which then becomes fragile. Damage caused by UV rays is even greater in fine hair as it is naturally less resilient than thick locks.

... And disrupt the scalp's balance

Like the rest of your skin, your scalp is sensitive to over-exposure to the sun. If it is subject to repeated exposure, its balance is disrupted and it ends up drying out and may even get sunburned. Hence the importance of wearing a hat in summer. When your scalp becomes too dry, your skin peels off and dandruff may start forming. This is "dry" dandruff. These small white particles detach of their own accord and fall onto your shoulders.

Be careful with hair colouring

Although lighter strands which naturally highlight your locks (without chemical products) look lovely, they are the result of the negative impact that UV rays have on your hair. By damaging the hair's structure, they prevent pigments from clinging onto the hair fibre. That's why your strands get naturally lighter without bleaching. If you have coloured hair UV rays can fade your colour, which is why your blond colour can turn brassy or your light brown hair turn red!