Beating the calories: plate sizes and our deceiving eyes.
As many may know, I’m currently training for my first full marathon which I hope to run in early July. I’ve signed up with a beginner marathon group, and have consistently run throughout January in order to start building strength.
My new coach has mentioned to me that I’d probably need to lose a bit more weight in order to adequately prepare for the marathon. It’s not something I was unaware of – I calculate that I’d probably need to be about 8-10kg lighter in order to perform to my full potential.
I’m already down about 11-12kg on my weight before starting running, and while I have no issues with running hundreds of kilometres, getting the diet right and reducing caloric intake has been an ongoing issue that has plagued me most of my adult life. My BMI suggests I’m in the overweight range, and my body fat percentage is not ideal. I know this, and I’ve been trying hard to get these down.
However, I’ve been spurred into doing some quick-fire research on how to solve the weight problem. An interesting 2010 article in the Physiology and Behavior by Brian Wansink entitled ‘From mindless eating to mindlessly eating better’ caught my eye .
Wansink’s basic argument is that plate shape, plate size and package sizes play a bigger role in determining food choices than many people realise. His research indicated that people, regardless of size and weight, were terrible at estimating the caloric content of food, inferring that when it comes to making choices based on sight, our eyes deceive us.
His conclusion is indicate that by removing items from our environment that make us make bad choices with regards to food (such as large dinner plates and smaller wider glasses), this will help us with portion control. He also talks about social norms and other cultural rules that influence the way we think about ‘how much is enough?’.
It’s an interesting concept that I’d been loosely aware of but never considered seriously before. Historically, portion sizes have been increasingly – and rapidly as well. Wansink does an interesting analysis of plate size from the year 1000 onwards (relying on art and some complex mathematical algorithm) concluding that we’re using bigger utensils and bigger plates and bowls than ever before. There seems to be a rough consensus – this analysis of plate sizes of cafeteria says, by reducing the plate size, one creates the illusion that they’re eating more. It seems that tricking your eyes will reduce your waistline.
I’m reminded of this simple adage coined by journalist Michael Pollan that seems to hold true with regards to food choices: Eat food. Not too much. Mostly plants. That’s a winning formula for good eating.
 Wansink, Brian (2010) “From mindless eating to mindlessly eating better.”, Physiology & Behavior, 100, i5, 454-463.