Portion distortion - Are your eyes are bigger than your stomach?

Why do people eat more than they need?

Managing your food portions is a vital component of weight control. Consuming too much of a food (even if it is healthy or low in kilojoules) leaves you with excess fuel, making it hard to maintain your weight, let alone lose it. It’s a challenge to remain conscious of how much you eat, and also know what is a suitable portion of different foods.

Dutch research conducted in 2009 suggests that portion sizes of foods eaten both inside as well as outside the home have increased over the last few decades. This may have gradually changed people’s perceptions and cultural norms, and led people to believe that larger portion sizes are appropriate. Individuals may also show considerable variation in what they perceive as a large or small portion.

Did you know? Portion sizes of foods eaten both inside as well as outside the home have increased over the last few decades.

The research

Not only does perception affect portion size, but so does the packaging size and utensils used. For example, when a person decides to eat half a bowl of food, the size of the bowl has an influence over the serving size consumed.

A 2006 American study found that larger bowls and spoons tend to make people serve more food. The researchers noted that although the amount of food people serve themselves requires cognitive thought, it is also driven by environmental factors.

Participants, who were nutrition experts, served themselves 31 percent more ice cream when they were given a 1000 millilitre bowl compared to a 500 millilitre bowl. Their servings also increased by 14.5 percent when they were given a larger spoon compared to a smaller utensil.

When subjects were given both a large spoon and big bowl, they served themselves 56.8 percent more kilojoules.

These finding were supported by additional American research from 2005 which found that large packages and containers can lead to overeating, even when the food doesn’t taste nice.

Moviegoers who were served stale popcorn in big buckets ate 34 percent more than those given the same stale popcorn in medium-sized containers. When the popcorn was fresh, people with the large tubs ate 45 percent more than those given fresh popcorn in medium-sized containers.

These studies highlight the fact that people are generally unaware of how larger portions and packaging sizes encourage them to eat more. And this affect even extends to nutrition experts who would be best equipped for estimating the average kilojoule content from different serving sizes.

Did you know? Research has shown that people can eat up to 45% more food when it’s served in large compared to small serving containers.

Adjusting for portion distortion

To reverse the trend towards larger portions and the associated higher kilojoule intake, there are some strategies you can adopt to control portion distortion.

These include:

• educating yourself on a healthy portion size of foods you commonly eat
• be aware of the tendency to overeat when eating out of large packets, or from large plates and bowls
• repackage foods yourself into smaller containers use smaller serving plates and bowls for breakfast, lunch and dinner use tall, narrow glasses for kilojoule laden drinks
• use smaller spoons when serving yourself, or when eating from a bowl
• when dining out, order smaller portions, and share entrées and desserts

Did you know? You can help to prevent portion distortion by repackaging foods into smaller containers, and serving food on smaller plates and bowls.

More tips on controlling your portions
For more information on portion control, click here to view an article from the Blackmores archive titled “Control your weight, control your portions”.