I have a 20-year history of skin problems on my forehead and temples. Some have been skin cancers that have been surgically removed. I am concerned that most shampoos cause inflammation on my upper forehead and know that most contain sodium lauryl sulphate (SLS) or similar ingredients. Can you please recommend shampoos that do not contain such ingredients.

Dr Fred Kavalier answers your health question:

SLS is a detergent found in almost all shampoos and toothpastes. The internet is full of suggestions that SLS causes cancer, but there is no evidence that this is true. SLS can irritate skin, and I'm sure if it is used in industrial quantities your skin will not like it. But I do not think that SLS is the cause of your skin cancers. SLS has been shown to be toxic, but not cancer-causing, in animals. But the amount that a human would need to ingest is enormous. There are some SLS-free shampoos on the market, but I'm not able to give recommendations, because I don't think there is any good reason to buy them.

Please mail your questions for Dr Fred to health@independent.co.uk. He regrets that he is unable to respond personally to questions.