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Ask the doctor: Is hair straightening safe?
Q. I had my hair straightened six months ago. Is there any danger in getting these treatments twice a year? I hear they may contain formalin or formaldehyde.
A. Like permanent wave solutions, hair straightening products are designed to break and reform the chemical bonds in keratin, the key structural protein in hair and nails. Permanent wave solutions make the hair more curly; hair straighteners, as the name implies, make it very straight.
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