The larger the serving size of food, or the container it comes in, the greater likelihood a person will eat more of it. This effect, called portion distortion, can easily lead to passive over-consumption and with that, real increases in the risk of obesity and its connected diseases.
It has been a fascinating field of research that has advanced over the last few decades that has studied that how food is presented, and the serving size given, can significantly affect how much of the food a person eats. Now researchers have combined the disparate research into a major scientific review with some stark conclusions.
Involving 72 research studies, the review looked at the influence of portion size, packaging size and tableware size on food consumption. The results were consistent in showing a greater likelihood to eat more food when the serving size, packaging or tableware were large compared to using smaller varieties of each.
Taking the research one step further, it was estimated that reducing exposure to larger serving sizes could reduce daily energy intake by between 12 and 16 percent for an adult living in the UK. In the face of the growing overweight and obesity problem, these are not numbers to be trifled at.
What was interesting from the research was that the susceptibility to eat more with larger food sizes applied equally to men and women. And this was regardless of their body weight, susceptibility to hunger, or tendency to control their own eating behaviour. What this means is that all of us are affected by the subconscious cues to eat more when we are presented with a larger serving size or food or when it comes in larger tableware.
Large serving sizes and bigger packaging sizes appeal to our ‘sense of value’. This is great if you were looking at buying washing powder for example. But in an environment that has strong drivers to promote weight gain, such ‘value for money’ behaviour seeking when it comes to food is to most people’s detriment.
How to fight back
So how to combat our innate tendency to overeat? Consider making a conscious choice to self-serve smaller portions of kilojoule dense foods such as desserts, drinks and fatty foods. Or eat food from smaller bowls, plates, or cups. When shopping, be wary of the ‘two for one’ or ’30 percent more’ label promotions on food, especially for confectionery and other snack items.
One of the leading researchers in the field is Dr Brian Wansink and he has lots of great resources on his website www.mindlesseating.org
naomi says
February 12, 2016 at 6:18 pmNot only portion sizes and packet sizes (in the supermarket) are large but I notice that pieces of fruit are bigger too. It is getting harder to find smaller apples, for examples or mangos, nectarines and peaches
Troy says
November 14, 2015 at 1:39 pmNice one Tim!
Brian Wansink’s book is a personal nutrition favourite for me and taught me lots about portion control a couple of years back, I still reference it and refer it to other folks.
Tim is this area looking into the more hedonistic patterns of eating rather than those maintaining energy balance? Given that the review seemed to apply to all kinds of folks, lean and obese, there appears to be more going on than just hormonal responses and that they’re somehow subconsciously overridden.
Also do you know, or have you heard of any recent development in leptin availability in those who aren’t resistant to it? Last time I heard it was around $500 USD (‘per day’!) to prescribe to those in need or who could benefit from it.
Tim Crowe says
November 14, 2015 at 2:14 pmThanks Troy and yes, there is a lot going on here and it is far more than just hedonistic responses – even the colour and shape of food serving containers can influence consumption so our subconscious has a clear role to play. As for your question on leptin, answer is ‘no idea’ – leptin was exciting in the early 90s but has not lived up to its promise as being a key hormone to look for and attempt to modulate in weight management.