Less than six months ago she came under fire when pictures of her looking worryingly skinny in a bikini surfaced online.

But despite the insistence from her personal trainer Harley Pasternak that Megan Fox struggles to put on weight, the actress appeared much healthier yesterday as she was spotted strolling around the set of her new movie.

The 25-year-old actress displayed a much curvier physique as she filmed scenes for This Is Forty in Los Angeles.

Looking better: Megan Fox looks much healthier on the set of her new film This Is Forty in Los Angeles yesterday

Dressed in a low-cut black vest top and unusual brown leather high-waisted shorts, the brunette beauty seemed to have more muscular legs than before as well as a more ample chest.

The Transformers star also looked fuller in the face.

Megan’s newly curvaceous appearance is a step in the right direction following a slew of negative comments claiming the actress was anorexic after her Armani ads came out showing her looking gaunt and bony.

Her trainer, Harley Pasternak spoke out in her defence at the time claiming she struggles to put on weight.

More curves: Megan appears to have a more voluptuous shape compared to earlier this year

‘She gets frustrated at times because she’s like “I need to put on weight.” So she actually weight-trains to keep on that lean muscle tissue,’  Pasternak told America’s Hollywood Life.

‘Believe it or not she has this really fast metabolism. So her training is all about body toning and sculpting. With her it’s really about she’s eating enough of the right things.

‘People thought, “Oh she must be anorexic”, but she’s far from that!’

Megan made her name by flaunting her shapely figure in the first two instalments of the Transformers franchise.

Better now: Megan slimmed down for her wedding and before she shot her famous Armarni campaign at the end of last year

But after getting married, the actress seemed to lose her womanly curves, instead displaying jutting hip bones and visible rib cage as she relaxed on the beach in Hawaii at the end of last year.

It was even rumoured that she had been fired from the films third episode after losing too much weight, as director Michael Bay didn’t think she could be sexy enough for the role any more.

Despite the personal criticism, the actress is hard at work on the set of her new project, said to be a spin-off of Judd Apatow’s Knocked Up.

Fighting fit: The actress came under fire for her slender frame but is looking far more curvy now

Apatow’s wife, actress Leslie Mann, recently said that the Jennifer’s Body star is ‘hilarious’ in her role.

‘Megan Fox is so funny,’ she said recently. ‘She’s hilarious. You wouldn’t, I don’t know if other people [expect it], but I think she’s really funny. You’ll be pleasantly surprised.’

Her role in the film is still shrouded in mystery, however. ‘I can’t say that part,’ Mann replied when asked to divulge script secrets.

The sexy brunette will also appear in Jennifer Westfeldt’s ensemble comedy Friends With Kids alongside Adam Scott, Jon Hamm, Kristen Wiig and Maya Rudolph.

Too slim: Megan bared her skinny physique in the Armani underwear campaign she shot last year

The actress had no curves and her hip bones and ribs were clearly visible