A woman's obsession with clean eating has led her to develop an eating disorder called orthorexia nervosa, which has spurred a movement that includes almost 70,000 Instagram posts on the trend.

35-year-old Carrie Armstrong was consumed by the urge to eat only fruits and vegetables and drink water, losing so much weight at that time that she was tied to wearing children's clothes.

It started when she contracted a virus eight years ago and attempted to speed up her recovery through dietary changes and alternative therapies. Her food fixation made her orthorexic, her hair falling out and her teeth crumbling.

"I didn't consume the food, the food consumed me," she recounted in an interview, citing her lack of balance and her staying in a wheelchair and hardly improving even with such interventions.

It was a mindset of extreme detoxification and not weight loss, according to Armstrong, who has since overcome the disorder.

Orthorexia nervosa was coined in 1997 and defined by Dr. Steven Bratman, himself a sufferer, as "a pathological fixation on eating proper food." But the condition is yet to be recognized by the Diagnostic and Statistical Manual of Mental Disorder as an eating disorder.

And there seems to be a push for this trend on social media. The hashtag "orthorexia" boasts nearly 70,000 posts on Instagram, with users exchanging tips and advice for clean eating. For charity Beat, there has been a shift from weight loss to the drive to be physically perfect.

"The increasing emphasis on body muscle and tone over and above size and shape may well be affecting the incidence of orthorexia," said Beat CEO Lorna Garner, adding there is more imagery on social media as well as greater marketing push for "fit" bodies.

Men can also suffer from this disorder, including California-based wellness blogger and author Kevin Gianni. He experienced orthorexia for almost six years on and off, becoming a raw-food vegan after becoming preoccupied with his family history of cancer.

His diet gave him debilitating cramps as well as anxiety and poor sex drive. "It is brainwashing. I had created and bought into this belief system that if I ate meat, I would eventually die," he recalled.

Gianni reintroduced other foods into his diet and now gets blood testing every year.

Sports nutritionist James Collins warned that nutrient deficiencies may result from diets that exclude whole food groups. He emphasized the need for context.

"The core principles of a diet might be good, but if you're applying them to someone who is training at the gym daily, working a 10-hour day, or has two children, energy levels are going to flatline," said Collins, who conducts blood tests for clients and probes their metabolism to spot signs of deficiencies.

Photo: Alex Lomas | Flickr