By SUSAN CALLAHAN, Associate Editor and Featured Columnist
The French phrase "trompe l'oeil" literally means to trick the eye. The technique usually is used to describe the use of intricate murals that are so realistic they fool your eyes. But, it turns out, that the food industry and dinnerware industry in the US have been engaged in a sort of master trompe l'oeil experiment for the better part of 60 years. And, voila, guess who the guinea pigs are --- you.
The year is 1960. Mom and Dad and 2.4 kids are sitting down to dinner. The food looks comfortingly familiar. But, look more closely, and you notice a subtle difference between the 1960 dinner table and the one you eat at today. The plates are smaller. In 1960, the average size of the dinner plates was 9 to 10 inches across. And something else was different. People were smaller too --- about 24 pounds smaller on average than we are today.
How things have changed. In 1980, no state in the US had an obesity rate above 15 percent. Even in 1991, no state had an obesity rate over 20 percent. Now, more than 30 percent of adults are obese, joined by about 17 percent of 2 to 19 year olds .
The 12th annual report from the Robert Wood Johnson Foundation in 2015 found that rates of obesity now exceed a whopping 35 percent in three states (Arkansas, West Virginia and Mississippi). Obesity rate are at or above 30 percent in 22 states out of 50 states. And, here's the kicker --- obesity rates are not below 21 percent in any state. Ouch.
What's worse, the 78 million Americans who are obese face a dismal list of health problems --- including diabetes, heart disease, and cancer and lowered life expectancy.
You Are Not Fat Because of Laziness
What’s going on here? We are not lazy. In fact, studies show that Americans are in fact the hardest working people on the planet, working an average of over 40 hours per week, according to the Bureau of Labor Statistics.
Clearly, what is moving our weight up collectively are powerful forces, some subtle and some not so subtle. Among the most powerful force pushing our weight up is portion size. In other words, it’s not just what we are eating. It’s that we are eating too much of it.
One of the most effective ways to limit portion size is to trick your eye by using smaller plates. Scientists have become better at figuring out why and when we are “full” after eating. Satiety is the name they give this phenomenon. Many studies have found, for example, that we become satiated --- full --- earlier if we eat the same meals over and over. Other studies have found that people tend to eat until they have cleared their plates.
But which influence is more important? Is it the food or is it the size of the plate that tells us that we are full?
Surprisingly, though both lay a part, it is the size of the meal that plays a greater role in determining when you stop eating, new studies show.
To put it another way, we humans would eat a platter full of food if a platter were put in front of us. We would eat a saucer plate full of food if a saucer plate were put in front of it. Until our eyes can see “all gone!” , we don’t stop eating.
Expected Satiety Is the Magic Key
Imagine it is dinner time. Plates are brought to the dining table. A plate is put in front of you. It is at this point, scientists say, that your mind takes a snapshot of the plate. Your eye takes it all in, and makes a quick calculation that the food in front of you is all there is, and it sets an “expected satiety” --- setting up the point at which you expect to be full. Much of the pioneering concept of what makes us feel full was developed by scientists at Cornell University in New York and the University of Bristol, UK.
We Are Being “Coerced to Overconsume”
What these studies have found is that, in the words of Dr. Jeff Bronstrum of the University of Bristol, we are being “coerced to overconsume” by ever larger portion sizes.
Probably the most famous experiment in this area came from Cornell University in 2005 involving a magical “bottomless bowl”.
In the Cornell experiment, 54 participants were sat at a modified restaurant-style table and given bowls of soup to eat. Some of the participants were given normal bowls.
But unbeknownst to a second group of participants, their bowls were rigged by a mechanism under the table to be self-refilling, filling up again imperceptibly as the soup was eaten.
At the end of the meal, the scientists totalled the amount of soup eaten. What they found was startling. Those who ate from the self-refilling bowls ate 73% more soup than those who ate from normal bowls.
Proving once again that the eyes are the key to how much you eat, in 2010 a team of scientists led by Dr. B. Scheibehenne from the University of Basel in Switzerland constructed another key experiment.
In a completely dark restaurant, 64 people were served lunch. Some of the people were given supersized portions. Without visual cues to guide them, the people dining in the dark ended up eating 36% more than the others. And, even after eating the super-sized meal, when they were offered dessert, they went for that too.
These studies confirm that our eyes and not our stomachs determine when we are full. To successfully lose weight, you have to be aware of the “picture” that you are giving your eyes at the very start of the meal. Your eyes in a sense measure and plan when you are going to become full.
And that brings us to the small plates.
Small Plates Are the Key to Losing Weight and Fighting Obesity
The average plate size in America is growing. In 1900, plates averaged 9 inches, in 1950 they were 10 inches and by 2010, the standard dinner plate in America had grown to 12 inches.
In Europe, the average plate size has stayed at 9 inches (with the exception being the UK, where the average plate size is 12 inches). Perhaps not surprisingly, obesity rates in many European countries lag the 30% current obesity rate in the US.
For example, Italy --- the home of pasta, no less --- has an obesity rate under 10% and France’s obesity rate, despite the heavy cream sauces and their liberal use of butter, is approximately 12.5%, similar to the rate for the US back in 1960, according to 2014 data from the OECD.
So, while the size of your dinner plate is not the only factor in weight loss, the takeaway from all these studies is that your eyes are a lot smarter than your stomach in controlling the amount you eat.