Kim Kardashian West has her own till button at her favourite deli.

The 'Keeping Up With the Kardashians' star often picks up a salad from Health Nut in California and despite always ordering the same meal, the store cashiers don't know what it contains.

Author Sean Smith, who is writing a biography of the reality star, told heat magazine: ''I was in Calabasas and I popped into Health Nut, the store where her family buy the salads they are always eating.

''I asked the guy at the counter for Kim;s favourite salad. 'No problem' he said, putting my order into the till and taking my money.

'''What's in it?' I asked. 'No idea', he said, 'I just hit a button marked Kardashian.' ''

While Kim - who is pregnant with her second child - has her favourite salad at the deli, she recently revealed she and husband Kanye West have hired a nutritionist who changes their meal plan regularly.

She said: ''Kanye loves to eat really healthy and is always on different diets. He has a chef who comes in the morning and cooks breakfast for both of us and gets our meal plans together for the day. We just started seeing a nutritionist who changes our diet every 10 days.

''I think after you have a baby you want everything to be as pure as possible. I want to set an example and to be natural and healthy. It's a decision Kanye and I made, to see a nutritionist together.