05 Oct 2016

The obesity epidemic is largely driven by ever-increasing food portion sizes. Yet efforts to fight overeating more often seek to influence what people eat instead of how much they eat. The focus is on warnings, labels, taxes and bans, which, while commendable, are seen by the industry as being bad for business and by consumers as reducing their right to eat what they want.

Food reformulation is part of the solution but it has two major limitations. First, it is rejected by many consumers who find it suspect, from both a taste and health perspective. Second, my research suggests that it creates a misleading “health halo”, which can backfire and actually lead to overeating. This suggests that marketers should only communicate about reformulation after it has been implemented and accepted.

I believe that understanding what drives our choice of portion size provides a unique opportunity to develop innovative ways to improve consumer health and wellness while preserving business growth and eating enjoyment. Below I outline two approaches that I will present at the Food Matters Live conference (and which are also available on my website).

Less size: Improve the perception of reasonable portion and package sizes

Food portions and packages have increased enormously. Not so long ago, a 16-ounce bottle of soda was advertised as large enough for three adults. Now, 16 ounces (or 50cl) are considered a normal single-serving.

Part of the reason why we accept this is that supersized portions appear smaller than they are because our brains are very bad at geometry. Increasing the height, width, and length of any object by 26% is enough to double its volume (because 1.263=2). Yet, because our brains tend to add (rather than multiply) the changes in dimension, we perceive that object to be only 50% to 70% bigger. The net result are huge portions that consumers don’t see and aren’t willing to pay for, overeating, and food waste, a total lose-lose scenario.

Unfortunately for food marketers, our brains are more accurate when it comes to downsizing because they now have two reference points: the original size and the knowledge that sizes are always bigger than zero. To encourage people to prefer - and pay for - smaller portions, one strategy is to add small sizes to the range available. Because size perception is relative, adding a new “small” makes the old “small” a “medium”, making people more likely to buy it. Another approach is to brand sizes in a way that communicates volume, like Starbucks branding its smallest size, the “tall” cup. Finally, my research has shown that elongating rather than shortening food packaging and portions masks size reduction and greatly facilitates downsizing.

More pleasure: Focus on the sensory enjoyment of eating rather than on satiation or value for money

The second approach focuses on making people choose and actually prefer to pay more for smaller portions. Most people choose large portions because they are good value and won’t leave them hungry. However, they forget that sensory pleasure peaks after the few first bites, and that it is the last bite that determines the overall enjoyment of the food. Hence, people often eat portions that are too large from a pleasure standpoint. Our idea was to simply ask people to remember the sensory experience that they had when eating hedonic food. This led school kids, French and American adults, and restaurant customers to choose the smaller portions of desserts that were actually the best size for eating enjoyment. Fat and calories information also made people choose smaller desserts but feel bad about it, reducing their willingness to pay for the experience. In contrast, more vivid menu descriptions made people choose smaller portions and feel good about it, making them willing to pay more for less food. That’s a triple win for health, business, and eating pleasure. 

Pierre ChandonDirector, INSEAD Sorbonne Behavioral Lab will be speak at the Food Matters Live conference on Wednesday 23 November on The psychology of food choice: what shapes our food preferences? and seminar session Packaging as an agent for dietary behaviour change.

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