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Although there is some debate about the safety and amount of formaldehyde used in keratin hair straightening treatments, many women who have struggled with curly hair and frizz love the results of the procedure. Keratin treatments are effective but are also expensive, with treatments ranging from $150 to $500 a session as of 2013. You can expect to need a treatment about once very four months. To protect your investment and limit your exposure to the chemicals as much as possible, it is important to take care of your hair after the treatment by following all of the instructions given by your hairdresser, including watching where you swim.

Taking the Plunge

Swimming in fresh water will not harm your keratin treatment. Chlorinated pool water and saltwater, however, can both shorten the life of the treatment. When swimming in the ocean or in chlorinated water, tuck your hair into a swimming cap to protect it and keep it dry. If you prefer, you can coat your hair with a keratin-infused conditioner product before swimming and simply rinse the conditioner back out after your swim. Always wash your hair with a shampoo free of sodium chloride and sulfate. If you are faced with an impromptu swim and don’t have a cap or conditioner with you, thoroughly saturate your hair with fresh water before swimming. Hair that is already waterlogged won’t be able to absorb any more water from the pool or ocean.