Protecting Your Skin When Swimming - How to Guard Against Chlorine

Chlorine and skin - why are they a toxic pairing?

Pool water contains between 1 and 3 mg/l of free chlorine - enough to kill bacteria, but also enough to steadily break down the skin's natural protective barrier. Chlorine dissolves the intercellular lipids in the stratum corneum, namely the ceramides, cholesterol and free fatty acids that form the "cement" holding skin cells together.

Dermatological studies have shown that just 30 minutes in chlorinated water raises TEWL (transepidermal water loss) by 15-25%. This means the skin loses moisture far faster than usual - hence that tight, dry feeling after leaving the pool.

Swimmer's xerosis - the swimmer's dry skin

The term swimmer's xerosis describes the chronic skin dryness seen in people who use the pool regularly. Symptoms include:

• Flaking skin, especially on the arms and calves
• Itching that worsens after bathing
• Fine cracks on the hands and feet
• A dull, greyish skin tone
• Increased sensitivity to cosmetics

Professional swimmers suffer from swimmer's xerosis almost universally. But even people who swim 2-3 times a week can develop the problem after a few months if they don't use proper protection.

Barrier cream before swimming - dimethicone as a shield

The most effective preventive measure is to apply a barrier cream before getting into the water. The key ingredient is dimethicone (polydimethylsiloxane) - a silicone that forms a thin, water-resistant protective layer on the skin.

Dimethicone works like an invisible "protective film":

• It stops chlorine from coming into direct contact with the skin's lipids
• It reduces TEWL by 20-30% even in chlorinated water
• It doesn't wash off easily with water (it requires a surfactant)
• It's hypoallergenic and non-irritating

Apply the barrier cream 10-15 minutes before getting into the water, over the whole body, paying particular attention to areas of thin skin: the face, neckline and the inner arms. Check our ingredient database to see which products contain a suitable concentration of dimethicone.

Chlorine and sunscreens - a dangerous interaction

If you swim outdoors, there's an important interaction you need to know about: chlorine can degrade chemical filters, reducing their effectiveness by as much as 50%. Avobenzone, one of the most commonly used UVA filters, is especially unstable in the presence of chlorine.

The solution? Mineral filters (zinc oxide, titanium dioxide) are far more stable in chlorinated water. Read more about the types of filters in our guide to SPF.

The order of application for an outdoor pool:

1. Barrier cream with dimethicone (base layer)
2. Water-resistant mineral SPF 50 (UV protection layer)
3. Wait 15 minutes before getting into the water

Cleansing after swimming - gentleness above all

When you leave the pool, your skin is already irritated by the chlorine. The last thing it needs is aggressive cleansing. Here's the protocol recommended by dermatologists:

1. Immediately - shower in lukewarm (not hot!) water. Hot water dissolves lipids even further
2. A gentle wash gel - pH 5.0-5.5, free of SLS/SLES, ideally with cleansing oils (syndet)
3. Don't use a washcloth - your skin is too irritated for mechanical exfoliation
4. Dry your skin by gently pressing with a towel - don't rub!

Don't forget about your hair, either: chlorine is just as destructive to hair keratin. Before swimming, wet your hair with clean water - wet hair absorbs less chlorinated water than dry hair.

Moisturising - a rich cream rather than a light fluid

After cleansing, a swimmer's skin needs intensive moisture. This isn't the moment for a light fluid - you need a rich, barrier-repairing cream.

Look for products containing:

• Ceramides - they rebuild the lipid cement (ceramide NP, AP, EOP)
• Cholesterol - the second pillar of the lipid barrier
• Hyaluronic acid - it binds water within the epidermis
• Shea butter or jojoba oil - they create an occlusive layer and prevent further water loss
• Panthenol (5%+) - it speeds up the regeneration of irritated skin

Apply the cream to slightly damp skin (within 3 minutes of showering) - this is the window in which the ingredients absorb best and "lock" moisture into the skin.

Protection against goggle marks

Swimming goggles are a necessity, but they can leave lasting marks and irritation around the eyes. The skin in this area is 5 times thinner than on the rest of the face.

How to minimise the problem:

• Choose goggles with soft, silicone gaskets
• Before putting them on, apply a thin layer of barrier cream around the eyes
• Don't tighten the goggles too much - just enough to keep water out
• After swimming: a cold compress for 5 minutes will reduce redness
• A cream with vitamin K + arnica helps the marks fade faster

A skincare plan for swimmers - in summary

Regular swimming is a fantastic sport, but it calls for a consistent skincare routine. The key rules:

• Before: barrier cream + mineral SPF (outdoors)
• After: gentle cleansing + a rich cream with ceramides
• Day to day: avoid retinol and AHA acids on swimming days (increased sensitivity)

Find the best barrier and moisturising products in our PurScore cosmetics search engine.