A study conducted by nutritionists and published in the January edition of Journal of the American Dietetic Association looked at various menu offerings at restaurants including Wendy’s, Ruby Tuesday, McDonald’s, Denny’s, and Domino’s Pizza. The results show that the average menu item was understated by 18% of calories. This is due to the variance in portion sizes, and food preparation.
The nutritionists also analyzed frozen foods under the brands Weight Watchers, Lean Cuisine, South Beach Living, and Healthy Choice. The calorie count was on average 8% higher than the listed amount on the package.
Companies don't seem to be intentionally trying to mislead consumers. The US Food and Drug Administration (FDA) allows for up to 20% variance on the printed calories from the actual calories in the product.