SCOOBY-DOO star Linda Cardellini has been exposed by hER ex-boyfriend for dumping him because he was too fat.

Actor Jason Segel, who is now a star of US sitcom HOW I MET YOUR MOTHER, has revealed he split from the ER actress after she poked fun at his weight problems.

Segel recalls, "(She) glanced at my naked body and said, 'We need to talk.' Then she dumped me.

"I thought she really liked me for me, so I'd gained 20 pounds."

But the split was the best thing that could have happened for Segel - it prompted him to embark on a fitness routine, including swimming and running, and shed the weight to land a role in a hit sitcom.