Colour blocking, like any other hair colouring technique, has the potential to be damaging to your hair, especially when vibrant and contrasting colours are chosen. This is because achieving such vibrant shades often requires a process called pre-lightening, where the natural pigments in the hair are stripped away to create a blank canvas for the new colours. Pre-lightening can be harsh on the integrity of your hair, as it involves the use of chemicals and can lead to dryness, brittleness, and breakage if not done carefully and with proper aftercare. Therefore, it’s essential to be aware that while colour blocking offers stunning and eye-catching results, it’s important to take measures to protect and maintain the health of your hair, such as using high-quality hair products and seeking professional advice to minimise damage and ensure a vibrant, long-lasting look.