The Science Behind Portion Power
The American College of Cardiology recently estimated that 90% of weight loss is achieved by reducing food intake, while just 10% is achieved by increasing physical activity. This means in theory, you could stow the yoga mat, shutter that ten-speed, and still drop 90% of your desired weight simply by eating less. So why don’t we all do this instinctively?
The American College of Cardiology estimated that 90% of weight loss is achieved by reducing food intake, while just 10% is achieved by increasing physical activity.
The Skinny on Serving Sizes
One likely culprit is the way your food is served. The Journal of the American Medical Association has found that American portion sizes have increased significantly since the 1970’s. In fact, the Department of Nutrition and Food Studies at New York University found that American portions today exceed the FDA’s serving size guidelines by a whopping 200 calories more per day. (By way of comparison, our portions now dwarf their French counterparts by about 25%.)
The World Health Organization has linked these staggering portion sizes with the expansion of the American waistline.
Portion Power
A key to eating less is portion control. Smaller portions contain fewer calories, and eating fewer calories is one of the better ways to get lean. Consequently a number of solutions have been devised to encourage better portion control, including restrictive diets and calorie counting. But interestingly, one of the most helpful approaches has also been one the simplest: use smaller plates.
The Dish on Plates
A study in the journal Appetite found that people clean their plates an astonishing 91% of the time, no matter how much food is offered, even if they are no longer hungry.
Why plates? Because our plates have gotten out of hand.
Plate sizes have been rising in the U.S. over the last 50 years: the average plate in the 1960’s was 9 inches. Today it is 12. (France, ever the throwback, measures in at just 10 inches.)
You may think all this expanding china has had little effect on your eating habits, but think again: a study in the journal Appetite found that people clean their plates an astonishing 91% of the time, no matter how much food is offered, even if they are no longer hungry.
The National Institutes of Health recommend replacing larger plates with smaller plates to eat less. “People eat what’s put in front of them,” they say. “Try serving food on smaller plates if you’d like to eat less.”
Bring on the Data
The evidence in support of portion controlled plates is strong:
- A study published in the Archives of Internal Medicine divided 130 patients with identical diets into two groups: one with conventional plates, and one with portion-controlled plates. Those using the portion-controlled plates lost 94% more weight than those who did not.
- The analytic minds at Google found the data in support of small plates compelling, and decided to introduce smaller plates in their cafeterias. The result: Google employees lost an average of 10-15 pounds without ever committing to a formal diet.
- In a series of six studies published in the American Journal of Clinical Nutrition, increasing portion size led to an increase in food and calories ingested. In just one example, increasing the portion size of a pasta entrée by 50% led to a 43% increase in intake, or 211 additional calories.
- A study published in Journal of the American Medical Association (JAMA) found that participants eating from large bowls consumed 56% more than those eating from small bowls.
Even the Archives of Internal Medicine has gone on the record, saying that because the number of calories consumed at a meal are a function of the serving size offered, the results of switching plates can be dramatic.
Slim Satiation
Despite the huge drop in calories associated with smaller plates, subjects were still satisfied and didn’t miss the extra food..
So the data look good and the science is sound, but is it viable? Countless weight loss strategies have been proposed and discarded over the years because they have a tendency to become difficult in the long term. Simply put, most diets are essentially an exercise in misery. What does the evidence tell us about portion control through smaller plates? Good things.
Despite the huge drop in calories associated with smaller plates, a study at the University of Pennsylvania found that subjects were still satisfied and didn’t miss the extra food. A study in the American Journal of Clinical Nutrition reported that subjects were often unaware that they had eaten more when given larger portions.
Portion and Proportion: Nutrition By The Numbers
Based on a recent study in Appetite, the data suggest that switching from a 12-inch plate to a 9-inch plate may help reduce caloric intake by up to 48%, or up to 275-350 fewer calories per meal. This calorie cut may translate to roughly 14-18 pounds over 3 months if the plate is used two meals per day.
What to Eat
Of course, not all plates of food are created equal. Energy-dense foods like cheeseburgers contain far more calories per volume than low energy-density foods like vegetables. Because eating low-energy-dense foods leads to feeling fuller on fewer calories, you may get even better results by managing your food groups in a smart way:
- Based on a recent study in Appetite, data suggest that moving from average energy density foods to low energy density foods while also moving from a 12-inch plate to a 9-inch, portion-controlled plate may help result in up to an additional 11% fewer calories, for a total of up to 59% fewer calories consumed, or up to 435 fewer calories per meal. This calorie cut may translate to roughly 23 pounds over 3 months if the plate is used two meals per day.
An Easy Way to Eat
If this all sounds a bit technical, take heart: the leading lights in America nutrition have already made it far easier with charts and graphs. In 2011 the USDA launched MyPlate, an initiative that depicts the latest recommended American diet as a plate in four sections.While developing our plate size, design and methodology, Slim & Sage has benefited from the generous advice of Stanford University's Thomas N. Robinson, MD, MPH, the Irving Schulman Endowed Professor of Children's Health and Professor of Pediatrics and of Medicine at Stanford University, Director of Solutions Science and Director of the Center for Healthy Weight at Stanford and Lucile Packard Children's Hospital at Stanford. Dr. Robinson's research on solutions to help prevent and control weight gain and the impacts of plate design on perceived portion sizes has greatly informed our Slim & Sage approaches.
Ciao Baby Chow
One interesting sidebar to all this research is that portion control may be especially helpful to women looking to lose the baby weight. The Mayo Clinic recommends eating smaller portions for weight loss after pregnancy.
Slim & Sage: The Perfect Plate
Slim & Sage let you eat less, and eat better, without sacrificing a thing.
