The size of our utensils and plates might actually distort our judgment when choosing portion sizes.
There have been a few studies proving that people eat more when given food on larger plates, presumably because they make portions appear smaller. The Journal of Experimental Psychology, for example, published a study in 2013 in which the authors found that people who ate with larger plates at a Chinese buffet consumed 45 percent more food than they normally would.
On that same token, people who eat with smaller utensils are more likely to eat more. A recent study published in the Journal of Consumer Research shows that people do not feel as satisfied when using smaller utensils, because they need to take more bites than someone using a larger utensil.
So what is the right portion size? The study concludes that “people do not have clear internal cues about the appropriate quantity to consume.” The main takeaway is that you should not let a restaurant’s plate or utensil sizes dictate how much you do or do not eat.