Lighten upHair Photobleaching & Genetics

Photobleaching is what happens when hair color lightens after long exposure to the sun. Some folks spray lemon juice in their hair for a beachy, sun-kissed look, while others have hair that lightens naturally after spending time outdoors.

How it works

Not only do the sun’s ultraviolet rays cause our skin to tan, freckle, and (ouch) burn, UV rays also break down the hair’s pigment molecules. Researchers have studied UV exposure through a diversity of hair colors and textures and found that the sun breaks down proteins in all hair types. While some hair types are more likely to lighten color than others, reducing the amount of time spent in the sun is important for everyone’s overall hair health.

The genetic link

So far, 23andMe scientists have identified 48 genetic markers that may influence hair photobleaching. There are hundreds of genes that influence hair color, and scientists have more to learn about the ones associated with photobleaching.

hair and sun

Did you know?

Photobleaching is pretty common among people with European ancestry. In a recent 23andMe study, a little more than 72 percent of customers who agreed to participate in research (and have European ancestry) reported that the sun lightens their hair.

Explore more

Curious whether your hair is likely to lighten after long exposure to the sun? 23andMe’s Health + Ancestry Service can shine a little light on whether you’re likely to experience hair photobleaching based on your genetics. Pick up our kit to learn if your hair is more likely to lighten with sun exposure.

Health + Ancestry Service Kit

Health + Ancestry Service

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23andMe Blog (2018, July 30). “Itching to See 23andMe’s New Trait Reports.” Retrieved October 30, 2018, from

Dario MF et al. (2015). “Effects of solar radiation on hair and photoprotection.” J Photochem Photobiol B. 153:240-6.

Furlotte NA et al. (2015). “23andMe White Paper 23-12: Estimating complex phenotype prevalence using predictive models.” 23andMe White Paper 23-12.

Lu Z et al. (2009). “Profiling the response of human hair follicles to ultraviolet radiation.” J Invest Dermatol. 129(7):1790-804.

Santos Nogueira AC et al. (2004). “Hair color changes and protein damage caused by ultraviolet radiation.” J Photochem Photobiol B. 74(2-3):109-17.