Rebel Wilson flaunts her 18kg weight loss in designer little black dress

Rebel Wilson slips into a little black dress as she flaunts her body transformation and impressive 18kg weight loss

Rebel Wilson is believed to have lost 18kg (40lbs or 2.8 stone) since kicking off her ‘year of health’ in January.

And the Australian actress flaunted her impressive weight loss while enjoying a day out in sunny California on Wednesday.

The 40-year-old showed off her slimmed-down frame in a little black dress by Alexander McQueen.

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All smiles! Rebel Wilson slipped into a designer little black dress by Alexander McQueen on Wednesday as she flaunted her incredible body transformation and estimated 18kg weight loss

Looking healthy and happy, Rebel smiled for the camera against the backdrop of the Hollywood Hills.

The Pitch Perfect star’s blonde locks were blow-dried to perfection, and she sported a neutral makeup palette.

Her designer frock clung tightly to Rebel’s slimmed-down physique, highlighting her impressive weight loss over the past eight months.

Black to basics: The Pitch Perfect star's blonde locks were blow-dried to perfection, and she had a flawless complexion of neutral-hued makeup on

Black to basics: The Pitch Perfect star’s blonde locks were blow-dried to perfection, and she had a flawless complexion of neutral-hued makeup on

'Love yourself': Earlier in the day, Rebel (left) also shared a cheery sing-a-long video with her Australian actor pal Hugh Sheridan (right) - who she sometimes trains with

‘Love yourself’: Earlier in the day, Rebel (left) also shared a cheery sing-a-long video with her Australian actor pal Hugh Sheridan (right) – who she sometimes trains with

Earlier in the day, Rebel also shared a cheery sing-a-long video with her Australian actor pal Hugh Sheridan – who she sometimes trains with.

The pair busted out a rendition of Justin Bieber’s Love Yourself in the car.

Rebel announced in January that she was embarking on a health journey, and has been sticking to her diet and exercise plan ever since.

'2020 is going to be called "The Year of Health"': Rebel announced in January that she was embarking on a health journey, and has been sticking to her diet and exercise plan ever since

 ‘2020 is going to be called “The Year of Health”‘: Rebel announced in January that she was embarking on a health journey, and has been sticking to her diet and exercise plan ever since

She's not shy! Fans went WILD when Rebel posted a bikini photo last month

She’s not shy! Fans went WILD when Rebel posted a bikini photo last month 

‘Okay so for me 2020 is going to be called “The Year of Health”,’ she wrote on Instagram at the time.

‘I put on the athleisure and went out for a walk, deliberately hydrating on the couch right now and trying to avoid the sugar and junk food which is going to be hard after the holidays I’ve just had but I’m going to do it!’

Rebel revealed in May she was trying to get down to her goal weight of 75kg (165lbs or 11.8 stone).

Goal: Rebel revealed in May she was trying to get down to a weight of 75kg (165lbs or 11.8 stone), with the help of her personal trainer Jono Castano (left)

Goal: Rebel revealed in May she was trying to get down to a weight of 75kg (165lbs or 11.8 stone), with the help of her personal trainer Jono Castano (left)