Is hair colour damaging to your health and hair long term?


Let’s get some things cleared up, colouring your hair at home is not for everyone. That is because some colours are too strong and should remain in the hands of a professional. Also some people can have a severe allergic reaction to hair colour. But the right colour on people who are not allergic is safe and easy to do.

According to Dr Mary McMillan, when it comes to hair colour there are no long term effects.

“I’m often asked if I’m worried about the long-term effects of exposure to the chemicals in hair dyes. The short answer is no. As long as they’re used properly the health risks are very small.

No scientific studies have yet found a conclusive link between use of hair dyes and an increased risk of disease – even in hairdressers, who are exposed to these products day in and day out.”

Dr Mary McMillan, senior lecturer at the School of Science and Technology, University of New England.

So how do you know if you using the colour properly? … It’s easy!

Step 1.   Find out if colouring you hair at home is right for you

Not all colours should be done at home. Some use harsh chemicals like bleach, others involve an application technique that is just too tricky to do yourself – like foils!

The rule of thumb is if you are only changing your hair more than 1-2 shades, you should get it done by a professional. Everything else – like covering greys, refreshing old colour, toning blonde hair – you can do it yourself at home.

Take our FREE colour consult to find out if your colour can be done at home.


Step 2.   Do an allergy test

Perform the test as follows:

1. Mix 2ml of Hair Colour with 3ml of Developer in the bowl provided.

2. Apply the colour mixture to clean 1 cmÇ area of skin behind the ear and a separate area inside the elbow.

3. Leave uncovered and undisturbed for 48 hours.

If there are any signs of rash, redness, burning or itching, rinse immediately – the product MUST NOT be applied and medical advice must be taken before colouring your hair again.

The absence of reaction to this test is no guarantee that an allergic reaction may not occur while colouring you hair in the future. However this test represents an important precaution. In case of doubt, medical advice should be sought.




There are no studies that show any conclusive link between hair colour and long term effects, however hair colour can be dangerous for those who are allergic to it. So make sure you do an allergy test before each colour application, and if you are concerned, get a professional to do your next colour.



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