KIM Kardashian West "cannot leave the house" without Spanx.

The 34-year-old beauty - who has 22-month-old daughter North with husband Kanye West - is so insecure about her recent weight gain, she can't bare to be seen without control underwear.

Speaking on 'Keeping Up With the Kardashians', she said: "Everybody thinks, 'She got her butt done and her hips done' and all this stuff.

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"I'm like, 'No, I'm legit 20 pounds heavier.'

"I'm so insecure lately. Seriously, just with my weight. I cannot leave the house without Spanx."

Kim's weight gain could be attributed to her love of fast food, as earlier in the episode she told her sisters a "life-changing" event had taken place - an In-n-Out Burger had opened in her neighbourhood.

And she later showed her older sister Kourtney Kardashian some pictures from a nude photo shoot she had taken part in for her website earlier that day.

She laughed: "We went to KFC on the way there." Can you believe it?"

However, Kim told her stunned sibling she only ate the chicken.

She added: "I didn't eat the potatoes or anything like that."

Shocked Kourtney quipped: "Just a fried, greasy bucket of chicken!"

And it seems her calorific craving didn't end there that day.

Kim admitted: "And then we went to In-N-Out on the way home."