The Step-by-Step Guide to Reversing Sun, Sea and Chlorine Damage for Your Healthiest Autumn Hair Yet

Stronger, shinier hair starts here

Post-summer hair repair Karin Teigl seen wearing Loewe red oversized square sunglasses, Baum & Pferdgarten red-and-white striped long-sleeve polo sweater, colorful playful beaded necklaces including a cherry pendant,
(Image credit: Getty Images)

My hair has never been as damaged as it was after returning from Coachella a few years ago. Days spent battling sandstorms, relentless UV rays, chlorine-soaked pools, glitter, and non-stop heat styling left it frazzled, knotted, and crying out for serious TLC.

Fast forward to now, and many of us will be facing a similar scenario (perhaps without the glitter) as we return from our summer holidays. Because while a beach escape or tropical getaway can do wonders for the mind, body, and soul, our hair rarely emerges unscathed.

“Summer is often a shock to the system—especially for the scalp,” explains Deborah Maguire, registered trichologist and co-founder of Seed & Soul. “UV exposure, saltwater, chlorine, sweat build-up, and air travel all disrupt the natural balance of the skin and hair. The scalp’s microbiome can become inflamed, oil production shifts, and you may notice more irritation, sensitivity, or even flaking.”

Lifestyle changes over summer also play their part. For some, sunnier months bring an abundance of fresh food, hydration, and rest—all a gift to healthy hair. But for others, it’s late nights, extra cocktails, erratic meals, wedding season stress, and long-haul travel. “All of this impacts the gut and immune system, and the effects often show up in the hair weeks later through increased shedding or a lacklustre appearance,” says Maguire.

So, what’s the solution? As we swap beach bags for trench coats, now is the perfect moment to restore and reset. Here, experts reveal how to undo a summer of hair damage and bring your strands back to glossy, healthy life in time for autumn.

Post-summer hair repair: an inside-out approach

For best results, you need to get to the root of the problem—quite literally. After months of sun, sweat, SPF residue, and styling product build-up, the scalp can become inflamed, sensitised, or even sunburnt. And without restoring balance here first, any effort you make on the lengths of your hair may be in vain.

"A clarifying treatment or pre-wash oil can help remove build-up and soothe inflammation, but if there’s increased shedding or signs of imbalance, you need to look internally," advises Deborah. "I always recommend a break from heat styling and a boost of nutrient-dense foods, alongside targeted supplementation to support the root causes."

A supportive supplement like Seed & Soul is designed exactly for this exact kind of recovery. "It supports stress regulation, our ‘gut garden’ immune balance and hormonal balance, all of which take a hit over summer," adds Deborah. "It’s not just about surface-level shine, it’s about strengthening the systems that grow the hair in the first place."

Rehydrate and restore shine

Once you have calmed and soothed the scalp, you can address any issues with dryness throughout lengths and ends. Chlorine strips the protective sebum from hair and can degrade keratin, leaving strands rough and more porous, while saltwater draws moisture out of the hair shaft, causing dehydration and a coarse, crunchy feel. Plus, UV rays break down proteins (keratin) and oxidise lipids and pigments in the cuticle, leading to colour fade, brittleness, and loss of shine.

Luckily, Deborah explains that surface-level hair damage like rough texture or dryness can improve in two to three weeks with the right treatments. Opt for formulas rich in humectants like glycerin to draw water in, and emollients, like shea butter or natural oils, to restore lost lipids. It's also a good idea to introduce a bond repairing treatment into your routine to strengthen the hair and rebuild its structural integrity.

Combat colour fade

Just as UV rays can darken and age the skin, they also degrade the pigments in hair—both natural melanin and salon colour. The result? Fading, brassiness, and a lack of vibrancy, especially when combined with chlorine, salt, and heat. It’s why a sun-soaked holiday often leaves even the glossiest colour looking washed out or uneven.

To neutralise brassiness, reach for a semi-permanent violet toner, while an at-home glossing treatment helps restore shine and depth to lacklustre tones. And if your blonde has developed that tell-tale greenish cast from pool water, a simple apple cider vinegar rinse can help dissolve the copper deposits responsible.

Know when to go pro

If your hair is severely damaged and at-home remedies haven’t helped, it’s time to call in the professionals. In some cases, a targeted in-salon conditioning treatment, like the Hair Rehab at Haug London, which combines a scalp scrub with an infusion of restorative actives, may be all that’s needed to bring your strands back to life. But if your ends are beyond repair, a post-summer trim is the quickest way to restore strength and ensure your colour looks fresh and healthy again.

Lottie Winter
Beauty Director

Lottie Winter is the Beauty Director at Marie Claire UK. With over a decade of beauty journalism under her belt, she brings a desire to cut through the noise and get to what really matters–– products that deliver, conversations that empower, and beauty that makes people feel like their best selves.