People tend to underreport their food intake by approximately 50% due to poor estimation of quantity.

“even lean people I was about to say for lean people would the same uh bias I mean bias might be the wrong word but would the same uh error in reporting still exists uh there so there there is an error it's less it's I think it's around 18% but even dietitians under report by about 10%”

“so the average Under reporting was by 50% % so they were Under reporting their energy intake by 50% on average um and that's right in line with a lot of the other studies most if we look at people who are overweight and obese most of them under report by 30 to 70% um the demographic of obese women tend to be at the higher end of that uh obese men tend to be at the lower end of that”

“people under report by like 50% and it's pretty consistent in the studies and people really take that as like an up front so well I'm not a liar yeah well I don't think that people are lying I think people are just really horrible estimators of what they eat”

“I don't think that people are lying I think people are just really horrible estimators of what they eat you know like if you ever want to be depressed go away on a serving of cereal or way out a serving of ice cream or a serving of peanut butter you know people when they do these these food recalls I mean a serving of ice cream is not a bowl of ice cream like a bowl of ice cream is probably three times more than a serving in terms of what people are actually taking in”

“Why people mislead themselves about food intake”

“People underestimate their calorie intake by as much as 1,000 calories a day—and overestimate how much they’re moving.”

“if you look at studies it's very consistent uh people under report their calorie intake by 30 to 50%”

“I think we look at ourselves with rolls colored glasses and we look at — serving sizes and we we tend to like just give ourselves a little more grace than we probably should”