Portion Size: Then and Now

If you’ve ever rummaged through the glassware section of an antique store, you may have noticed how much smaller the cups, bowls, and plates are compared to more contemporary ones. New dinnerware has grown to accommodate the increasing volume of food and drinks we consume at each sitting.


Just looking at drinking glass sizes gives us an indication of how portion size has changed.


In the 1950s, coffee cups were made to hold a 6 oz cup of coffee (now, a small at Starbucks is 12 oz), and juice glasses were made to hold 5 oz of liquid (now a serving size for juice is 8oz, although we often pour more than that).


If it is true that we fill our plates and cups as a gauge for how much we should be consuming, maybe we would be better served eating off of the dinnerware from decades past!


It’s not just the glassware, and thus our at-home portions of food, that are changing. Restaurants have also increased portion size to keep up with our attraction to quantity and “value”. Look at the difference between a bagel today and one in the past:



The change in portion size isn't just limited to baked goods; the image below from the CDC shows the trend of "portion distortion":




Portion Size vs Serving Size


The serving size of food (what is recommended to eat at one sitting) and the portion size (the amount we actually eat) are often at odds.


Many people base their portion size on the amount that is served to them, or what looks full on a plate. This is in part why the USDA replaced the food pyramid with MyPlate as a guide to how much (and what) we should be eating at meals.


Another way to gauge how much we are intended to eat is to look at the serving size on food nutrition labels. This of course, works best when you are cooking at home. Monitoring serving sizes not only helps with portion control, but it also better reflects your consumption of vitamins and minerals.


However, if you monitor serving sizes, you probably have experienced the shock of realizing what we eat or drink in one sitting may be two or three times the amount reflected in an item’s nutrition label.


Why do serving sizes seem so small? The FDA started mandating food labels be placed on food items in the early 1990s. To determine the serving size, companies used a typical portion from the 1970s and 1980s. Although people are eating more per sitting now, we are still using the same portion size to determine serving size today!


Because of this discrepancy and the rise of obesity in our youth, the FDA has recently changed food labels to highlight calorie content and added sugars and change the serving size to better reflect the quantity we actually eat. Hopefully, with labels changing, so will our eating habits.


If you’re not used to looking at nutrition labels, here are some serving sizes of common food items that may surprise you.


Ice cream: ½ cup. Try measuring that the next time you dish up a scoop!


Peanut Butter: 2 tablespoons


Chicken: 1 oz (or 1/3 of a boneless, skinless chicken breast)


Avocado: 1/5 medium avocado


Tortilla chips: 10-15 chips


Dry cereal: 1 cup


WebMD has a great printable portion control guide that helps put serving size measurements into sizes we are more familiar with (for example, 1 cup of dry cereal should be the size of a baseball). You can download it here.


If you’d like this information in kid-terms, this video snippet from our “Way to Grow” program can help.


What strategy do you use to determine how much you eat? MyPlate? Serving size? Feeling of fullness? Available food?