Ever gone to the grocery story intending to buy apples and milk and left with a jar of queso dip, a gallon of ice cream and an enormous bag of Halloween candy? Impulse shopping can wreak havoc on your healthy eating plans, but experts say it may not be entirely your fault.An editorial published in this week's New England Journal of Medicine blames part of the obesity epidemic on our food environment. Dr. Deborah Cohen and Dr. Susan Babey collaborated to write the article "Candy at the Cash Register - A Risk Factor for Obesity and Chronic Disease.""The reality is that food choices are often automatic and made without full conscious awareness," the authors write. "In many cases they may even be the opposite of what the person deciding would consciously prefer."Advertising encourages spur-of-the-moment emotional purchases that are triggered by seeing the product, according to the editorial. The way food is arranged in a grocery store can have a big impact on what consumers buy. A 2009 study showed products placed at the end of the aisle account for 30% of all supermarket sales."People lack the capacity to fully control their eye gaze, and what they look at the longest is the strongest predictor of what they will buy," the authors write.Cohen and Babey propose treating product placement as a risk factor for obesity. Comparing it to safety regulations for a building, they write: "Although people could certainly stay away from the edges of balconies and not lean out of windows, mandatory railings and window guards protect them from falling ... (regulations could) govern the design and placement of foods in retail outlets to protect consumers."