Health of hair is really important. The chemical makeup of straightening services isn’t kind to the hair and with repeated or long term exposure can be harmful to health. There is also the consideration of whether you have or are planning to colour hair in the near future. Applying a chemical treatment on top of hair colour can lighten existing hair colour due to the strength of the chemicals which might leave you with an undesirable colour. Additionally if your intention is to colour your hair following a chemical straiaightening treatment, the results might be limited due to your stylist not wishing to compromise the integrity of your hair.