A former Qantas flight attendant has shared a sneaky secret on how to get an ever-elusive upgrade on your next flight.

Nik Loukas claims that anyone with a special meal request won’t be bumped up to business.

"If there's a special meal request in your booking, the airline won't even look at you (for an upgrade)," he told Business Insider. "Because you've got a dietary requirement, and they might not be able to cater for you if they upgrade you."

But the revelation has been disputed by a couple of different airlines.

A spokesman for Qantas told Traveller: "This is untrue and the type of meal our customers order has no bearing on their ability to be upgraded. If the upgrade is awarded, the special meal request will be provided in their new cabin."

According to The Telegraph Virgin Atlantic disagrees too.

"This isn't true - dietary requirements have no impact on upgrades," said a spokeswoman. "If a customer orders a special dietary meal we can serve it in any different cabin."