Always read the labels of the shampoo you buy, says Pat Thomas in the book What’s in this stuff? The writer says not to use shampoos that contain formaldehyde-forming agents and amines.
Here is another way to dilute your chemical hair washer! Says Pat : half fill an old shampoo bottle with your regular shampoo. Top up with an equal amount of water or a strong herbal infusion (such as chamomile) mixed with one tsp. of coconut oil. Olive or jojoba oils are also good choices. Add 1-2 tsp. of table salt to thicken the mix or add good old one to two teaspoons of sodium bicarbonate to soften the water and aid rinsing. Dissolve this in water or tea before mixing.)
This mixture will still foam well, and clean and condition your hair too. Give it a shake before using. Another safe choice for washing your hair and body is using castile soap or pure vegetable oil soap. These are also cheaper!