Shampoo and Style Straightened HairQ: How soon after thermal straightening can I wash/wet/style my hair? Also, I have had this procedure done 4 times in the last 2 1/2 years, and each time my hair gets thinner and flatter to my head, is this normal?
A: Typically it's suggested that you wait 2 days before shampooing the hair. This would also mean getting it wet as well. The primary reason for this is to allow the hair to normalize on its own without the effect of the water, shampoo, conditioner, etc. If you want to engage in wet styling (roller sets, and the like) you'll want to wait the 2 days as well.
As for the continued "thinning and flattening", you have to bear in mind what the thermal reconditioning does. The process is designed to contract/condense the cuticle layer of the hair to make it smooth. Doing this effectively reduces the diameter of the hair shaft. It is logical to think that repeating the process on hair that has been treated previously in such a manner would increase the effect - to a point, anyway. There is a minimum diameter to be achieved. It's likely that your hair seems to keep getting thinner and thinner because in the periods between treatments your hair is likely swelling in small increments back to what is more normal for you.
Unless you are using the term "thinning" to refer to an actual decrease in hair density (the number of hairs per square inch on the scalp) you should have nothing to worry about. If you do mean that you are experiencing a decrease in hair density, you should stop getting the treatments.
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