How hair colour is made — and why it fades
Summer can be beautiful, but the recent heatwaves across Europe were a reminder that extreme weather is now part of everyday life. Applying SPF to our face has become second nature — yet the scalp and hair are usually left unprotected. And that is exactly where one of the key processes shaping hair colour plays out: the battle between melanocytes and oxidative stress.
Hair colour comes from melanin, produced by melanocytes inside the hair follicle. With age and external factors, melanocytes gradually lose their ability to make pigment, and hair grows back without colour. That is why greying first appears “from the roots”.
Oxidative stress — one of the main causes of greying
Research into the greying process points to the central role of oxidative stress. Hydrogen peroxide (H₂O₂) builds up in the follicle while the enzymes that break it down — such as catalase — decline. An excess of free radicals damages melanocytes and disrupts the melanin production pathway. In other words: greying is not only a matter of genes and age — it is also the result of accumulating oxidative damage, something we can genuinely influence.
Where do climate and heat come in?
High temperatures, UVA/UVB radiation and air pollution intensify oxidative stress on the scalp. Cosmetic-industry experts — including Croda, within its Climate-Adaptive Beauty trend — highlight that the scalp is an extension of facial skin and just as exposed to UV, yet we rarely protect it.
The conclusion follows naturally: if oxidative stress is one of the main causes of greying, and heat and UV intensify that stress, then extreme climate puts strain on the very mechanism responsible for hair colour. Let us keep it in proportion — there are still few clinical studies measuring exactly how much grey a given heatwave season adds — but the causal chain itself (UV and heat → more free radicals → strained melanocytes) is well documented. So in summer it is worth treating your scalp the way you treat your face.
Prevention: how to protect colour at the source
- Shield your scalp from the sun — a hat, a change of parting, products with UV filters.
- Reduce factors that increase oxidative stress — cigarette smoke, smog, aggressive treatments.
- Support the follicles antioxidatively: from within (an antioxidant-rich diet) and topically.
Ethne peptide serum — melanocyte support and an antioxidant shield
Ethne serum is built around the smart lipopeptide SILVERFREE™ (Palmitoyl Dipeptide-52, Sederma). It works on two levels: antioxidant support — helps neutralise free radicals generated by heat and smog, protecting follicles from premature ageing; pigmentation support — stimulates melanocytes to produce melanin, supporting the return of your natural shade (from blondes to deep black), without artificial dyes. A vegan, ultra-light formula (98.9% naturally derived ingredients per ISO 16128) based on bitter orange flower water. The efficacy of SILVERFREE™ was confirmed on 84 volunteers across four independent studies.
What to expect and how to use it
Apply once a day to a dry or towel-dried scalp (4 doses with the pipette), no rinsing. First results — improved texture and shine — are usually visible after 4–8 weeks, with a more noticeable return of natural colour after 12–16 weeks, depending on hair length and growth rate. A full course lasts about 16 weeks (4 bottles), and the effect holds for at least 4 months after finishing.
Discover the Ethne peptide serum
References
- Wood J.M. et al., “Senile hair graying: H₂O₂-mediated oxidative stress affects human hair color by blunting methionine sulfoxide repair”, FASEB Journal, 2009.
- Croda Beauty, “Preventative hair care: protecting from environmental aggressors”, Climate-Adaptive Beauty, 2025.
- Sederma / Croda — SILVERFREE™ (Palmitoyl Dipeptide-52) ingredient data.