Q. My medium length hair is quite dull and a bit damaged. A friend said it might be a good idea to use a heat protection product because I blow-dry it every day and use tongs. Can you explain? A According to celebrity hairdresser Jonathan Long, ‘it is extremely important to apply protection when you use any heated appliances to keep your hair looking healthy and shiny. Heated tools typically get up to 210 degrees C, which you then put directly on your hair. That causes a lot of damage to even the strongest hair types. The result is dry, dull, damaged hair.’

‘What’s more,’ says Jonathan, who is co-founder of Chelsea salon Lockonego (www.lockonego.com), ‘not only does the heat damage the actual fibre of the hair, it can also break down the pigment within the hair shaft, changing its colour.’ Frizziness and split ends are other side effects as the heat evaporates the internal moisture in the hair.

The products work by adding an extra protective layer, which absorbs some of the heat so it has less impact on the hair fibres. Jonathan recommends Redken Satinwear 02 Prepping Blow-Dry Lotion/£14.30 for 160 ml, which contains hydrolysed wheat protein to protect up to 450 degrees heat, also defending against colour fade. ‘One pump, the size of a five pence coin, is all you need: apply to towel-dried hair before blow-drying. Adjust the amount depending on your hair thickness and length but beware of applying too much product or it will weigh down the hair.’

Another of Jonathan’s kit essentials is Redken Pillow Proof Blow Dry Express Primer/£14.30 for 170 ml, which locks hair in a protective 'thermal blanket' of flexible silicone resin and also helps to repair hair from the inside out. As a bonus, it reduces blow drying time by 50 per cent.’