So, how's your diet? Odds are you overestimate how healthy it actually is. The British Journal of Nutrition recently published findings from researchers in Japan and the United Kingdom. They asked a large number of people about their eating habits and also tested people's urine samples for certain food markers. Based on people's statements about their eating the researchers could find no links between diet and rising obesity rates. But when they tested the urine, they found lots of connections between bad eating and weight gain. More or less, people were terrible judges of their own eating habits. Study author, Kentaro Murakami, PhD, of Japan's University of Shiga Prefecture, says we tend to exaggerate the good foods we eat while we underestimate the bad. Self reported diet data is notoriously unreliable. A study from Harvard Medical School asked people to guess how many calories were in a meal. 1 in 4 people underestimated the meal by 500 calories or more! What explains this tendency? Well, we are all equipped with a self bias that champions our behaviour while being extra hard on the behaviours of others. A study at Stanford found that when asked to compare themselves to "the average American" people rated themselves as 27% better in 9 different categories. This bias is apparently stronger in uninformed people or those who have little knowledge of the topic at hand. The "Dunning-Kruger Effect" (named for the two researchers who first wrote on it) shows that the less someone knows on a subject, the more bullish that person will be when it comes to their own thoughts and behaviours. How do you overcome this self bias? Brian Wansink, PhD, director of Cornell University's Food and Brand Lab, says avoiding mindless eating is a good way to start. Many of us keep snack foods readily available. They are on our desks, sitting on the kitchen counter. It allows us easy access and can lead to snacking all day long. Even if we are careful at meals, this snacking adds up. Wansink recommends hiding your food. Put it in cupboards or drawers or places you can't see it unless you are looking for it. He also recommends eating from smaller plates and chewing gum as great ways to avoid overindulging. Think hard, are you honest about your diet?