Robert Downey, Jr. reached out to X-Men star Hugh Jackman after landing the lead role in Iron Man so they could swap diet tips.

Jackman famously bulks up for his role as Wolverine in the superhero films, and Downey, Jr. was keen to take advice on how to improve his physique.

The Australian actor tells Britain's Notebook magazine, "Half of Hollywood (plays superheroes) now... When Robert (Downey, Jr.) first got the part of Iron Man he reached out to me and said, 'Mate, can you just share with me the diet and how to get in shape?' because he knew I wasn't in shape before it, so there's a little bit of that (sharing that goes on between actors)."