Owens, who took charge of the 2015 RWC decider between New Zealand and Australia at Twickenham, has previously revealed he attempted to commit suicide as he struggled to understand his sexuality before coming out as gay.
And the courageous Welshman, arguably rugby's most high-profile match official, has taken part in a BBC television programme about male eating disorders to urge others suffering from similar problems to seek help.
"I've spoken about dealing with bulimia in the past but have never before revealed that to this day I continue to struggle with an eating disorder," he wrote in an article on the BBC website to accompany the broadcast.
"Since the age of 18, I have had bulimia nervosa.
"In 2015 I reached the pinnacle of my career - I refereed a World Cup final - in a memorable match between New Zealand and Australia.
"I'm known for being a steely, authoritative and, I hope, fair referee. As I walked onto the pitch that day, no-one would have believed that I was battling the creeping return of my bulimia.
"In the run up to the Rugby World Cup, I'd been under huge pressure to reach certain fitness levels - you have to reach an advanced level on the Yo-Yo Endurance Test (a variation on the bleep test used to measure physical fitness).
"Once I'd passed the test, I resumed a good routine of fitness and nutrition and went into the Rugby World Cup in peak condition.
"But the following year, the pressure was off and I notice I was putting on weight and so the bulimia returned.
— Nigel Owens MBE (@Nigelrefowens) July 21, 2017
"For those who are caught up in eating disorders and say there's nothing they can do about it, I understand what they are saying because it takes you over and you feel there is nothing you can do.
"But I would urge anyone suffering to do something - seek professional advice, tell people about it, don't hide it, don't lie about it, that's a great first step."