Illness and Hair Coloring and BleachingQ: Is it true that if you are sick your hair won't take very well if you are bleaching/coloring it?
A: I have never heard of any specific problems with color or bleaching processes being affected by illnesses in the client, but if a person has a medical condition that causes a change in the hair (makes it more porous, less porous, leaves it dry and brittle, or overly oily) this can affect the ability of the chemicals to penetrate the hair shaft.
Sometimes the changes involved with illness can develop rapidly - such as increased oiliness. Other forms of change that can result from illness only develop with prolonged sickness and are only seen with the new growth of the hair. For example: someone who has been ill for a long time may notice that their hair seems to be drier and rougher in texture at the scalp area.
Dryness and increased porosity can cause color processes to more easily damage the hair and can lead to uneven results. Conversely, resistant hair, or hair that is overly oily can result in under-processed color and uneven results as well.
Hair coloring and bleaching
Medications that affect your hair
Can thyroid medicine affect blond hair color?