What is the harm of using kelp to dye hair for a long time?

There are dangers such as allergic reaction and hair damage.

1, allergic reaction: Some people will be allergic to the ingredients in kelp hair dye, resulting in itchy scalp, redness, pain and other uncomfortable symptoms.

2, hair quality damage: the chemical composition in the hair dye will make the hair lose its natural protective layer, resulting in dry, fragile and easily broken hair, which will cause hair loss in severe cases.