Earlier this week, US site Into the Gloss answered a burning question – how do you get to look like Kim Kardashian? – by interviewing her about her beauty regime.

The whole interview is mesmerising. But beyond all the brouhaha about the cost of the contents of her makeup bag, which Jezebel totted up to a whopping $1,977.75 (around £1,290), the most interesting revelation (and the only free tip) is that Kardashian only washes her hair every five days.

“We start out with a blowout on day one,” she told the site, “then we go into a messier vibe the next day, and then we flat-iron it and do a really sleek look on day three since that requires a little oil in the hair. Day four could be a slicked-back ponytail, and on the fifth day is when you wash it.”

While she’s no advocate of the no-poo movement, it begs the question as to whether this is the ideal hairwashing routine? Andrew Bidwell, hair stylist at Atherton Cox who specialises in thinning hair, thinks for some hair types (like Kim’s) “it is exactly that”. He explains:

I wouldn’t call Kim Kardashian a ‘hair ambassador’ by any stretch, but her regime is pretty solid, especially because it utilises the natural state of the hair. Hair washing is very individual so there is no perfect amount, but if you have normal to dry hair, which Kim’s hair appears to be, then every five days is a good idea. It also explains the way her style changes – her signature look is that high ponytail which presumably falls on day three or four.“For some people with skin conditions such as dandruff, you will probably need to wash your hair more often. If you have psoriasis it’s best not to wash too often, and to avoid using a silicone-based shampoo, because this can cause an itchy or flaky scalp. Most shampoos contain silicone – it’s what gives hair that extreme gloss and shine – but it contains the same stuff that they use in the hydraulic system in car brakes and that’s not good for hair.

If your hair is finer than Kim’s, then you will probably need to wash your hair more often, say every other day, but you should only wash the scalp level, so it’s best to stick to the part underneath. If you wash your hair all over it will end up dehydrated.

Every five days might not seem much, but there is an argument for not washing your hair at all provided you live in the right environment. When I lived in rural France I never washed my hair, just rinsed it thoroughly. But the moment I came back to London I had to start again – it stank of cigarettes and got very dirty very quickly.

I have one issue, the flat ironing, which isn’t great. But her hair looks remarkably undamaged so she must be doing something right.