Which one would you choose? The healthy option or the chocolate bar? Perhaps your head says apple but your stomach says chocolate. If I told you the apple has 59 kilocalories and the Twix has 246, 18% of you would choose the apple. If I told you the apple has 247 kilojoules and the Twix has 1,029, 41% of you would choose the apple.
When people are faced with healthy versus unhealthy choices the way in which nutritional information is presented influences that choice. If you test this in people with a low prior interest in energy information the probability of choosing the apple increases from 3% to 59%.
We are exposed to this type of unit effect all the time. When we buy something for £9.99 we focus on the £9. When you are told a product costs just £1 a day rather than £30 a month and when a waiting time for treatment is 18 weeks rather than 4 and a half months.
The way we present information has a significant effect on the choices people make so we should consider that when giving health promotion advice.
How to Make a 29% Increase Look Bigger: The Unit Effect in Option Comparisons
Dr Richard Bogle
The opinions expressed in this blog are strictly those of the author and should not be construed as the opinion or policy of my employers nor recommendations for your care or anyone else's. Always seek professional guidance instead.