Plus all the variables in the lifestyle associated with different diets. Diet soda probably doesn't actually cause weight gain, but people turning to diet soda probably eat poorly already. This also only seems to show food intake percentages but not the total calorie intake. So do the high carb eaters just eat one potato per day? And the high fat eaters 6lbs of pork? This a multi dimensional problem needing more data to find the real trend. I mean, people with gun permits have a higher chance to be shot by a gun. Is it because the permit shoots the? Or is it because permit holders are more likely to be in a place where guns are more common?