EATING disorders are the type of thing many parents keep a keen eye out for among teenage girls - but with a quarter of those affected estimated to be male, the illness often goes unchecked among young men.

You only have to look at the recent trend for anti-diet books - those that explore themes like intuitive eating and self-image - to notice there's a pretty stark gender divide, with many written by and aimed at young women.

The stigma around men and eating disorders is something author Sam Pollen, 30, knows all too well. At age 12, he became gripped with anorexia, and says he struggled to find an authoritative voice to relate to.

"I remember struggling with that a lot as a teenager," Pollen recalls. "I wanted someone to be on the same page - someone to relate to."

NHS Digital data recently reported that the number of adult men being admitted to hospital with an eating disorder has risen by 70% over the past six years. Pollen believes that although it's never been a more pressing issue, the lack of understanding around the topic can often be a barrier for men to speak out.

Recalling the beginning of his anorexia, he says: "I was definitely a conscientious kid who worried a lot about things. I was quite anxious about making friends, doing well in school and all of the things that kids tend to worry about as they're getting older.

"I was also quite sporty and I liked running, but I became conscious about my body and slowly began running every day."

It was while on a family holiday in Italy that Pollen began to practice restricted eating. "I kind of had this kind of epiphany where I realised, 'Oh, you don't have to eat'," he recalls.

"It sounds ludicrous but these thoughts go through your mind with eating disorders. Over a period of months, it made me disordered and dysfunctional - often you don't realise it until it is very far gone."

Almost two decades since his recovery, Pollen has now written a young adult novel, The Year I Didn't Eat, to help other young boys who are struggling with issues like anorexia and bulimia. The book follows the story of Max, a 14-year-old boy who documents the highs and lows of life with an eating disorder over a 12-month period, and how if effects his family and friends.

Although it's a work of fiction, Pollen says he drew on many of his own experiences while writing it.

"The overwhelming thing I always remember from that time, is spending a great deal of time on my own," he says. "So many social occasions revolved around food, like going out for a meal or getting popcorn at the cinema. I didn't go out with my friends. I read a lot and played video games - the stuff kids usually do, but with none of the social interaction."

As well as helping others, Pollen says he also felt motivated to give a voice to a problem which is still shrouded in stigma - the charity, Beat, suggests that the exact number of men suffering from eating disorders in the UK is unknown, as many cases still go undiagnosed.

"I wanted to write the book because, now more than ever, eating disorders with men and boys is on the rise - it's something people should understand and have an insight into," says Pollen.

"It's the experience people talk about less... The result is that people recognise it less."

Ultimately, Pollen says he'd like to see more voices in the eating disorder conversation - not just from other men like himself, but from all ages and demographics.

"Looking back, I'm surprised - when I talk to people who knew me at the time, they say that they had no idea I had anorexia," he says. "When I see photos of myself, I am very obviously ill - but boys don't look at each other and talk about their bodies in that way.

"I've noticed that people of all different ages struggle with eating issues. There's a crazy number of people in retirement who suffer with eating disorders, because it's such a big lifestyle change. That's something that is rarely spoken about," Pollen adds. "We're talking about hundreds of thousands of people suffering - where can they turn?"

When it came to his own recovery, Pollen said having his friends and family keep the structure of his life in place was fundamental to getting his life back on track, which became a theme that's recurrent throughout Max's story in the book.

"One thing that matters a lot with eating disorders is early intervention. Eating issues are so habit-based, so it's good to talk it through. They develop and become harder to deal with, and that's why there's a recognition issue.

"My parents kept taking me to my grandparents, where we played board games together and we went on family walks. My friends kept asking me to do things, even though I had been saying no to them for a year. I had a life to fall back into during recovery. It was so significant to me."

His advice to parents is simple: "Keeping conversations about other stuff going is really important - pick topics that are not going to be upsetting and difficult.

"It's such a hard thing to approach, especially having that sort of open relationship - but there's no magic fairy who helps you to do it.

"It's also about not being too hard on yourself," says Pollen. "Even if you've done everything right or haven't done anything particularly wrong - it's not something parents should feel guilt for."

The Year I Didn't Eat by Sam Pollen is published by ZunTold, priced £7.99. Available now.