People who post pictures of almost every meal they eat to social media may have a deeper medical issue, according to the mental health chair for the Canadian Obesity Network.

Speaking at the Canadian Obesity Summit in Vancouver Wednesday, Dr. Valerie Taylor said many post pictures of food because they enjoy it, but some do it because food plays a significant role in their lives.

"You don't take pictures of who you're with, you take pictures of what you're eating," Taylor said.

"For some people who have the predisposition for weight behaviours, it just goes that one step further, and they start to develop unhealthy weight disorders and they start to have weight problems."

Taylor said people don't eat food for its nutritional value alone.

Research has shown food has a more psychological role in people's daily lives, which is one of the main causes of obesity today, she said.

Taylor, whose presentation to the conference was entitled "Food Fetish: Society's Complicated Relationship with Food," is an associate professor at the University of Toronto and psychiatrist-in-chief at Women’s College Hospital in Toronto.