According to a study I recently co-authored in Retail Magazine, understanding the calorie content of foods does not help people understand which foods are healthier. When study participants considered calorie information, they rate unhealthy foods as unhealthy and healthy foods, while healthy foods were less healthy. They are not sure about their judgment either.

In other words, calorie labels do not help participants judge food more accurately. This makes them themselves the second guess.

In nine experiments with more than 2,000 participants, my colleagues and I tested how people evaluate food using calorie information. For example, participants looked at foods that were often considered healthier, such as salads, or often healthy foods, such as cheeseburgers, and were asked to assess the health of each item. Participants correctly saw the huge gap between healthy and unhealthy foods when people didn’t consider calorie information. But these judgments become more gentle when they consider calorie information.

In another experiment in this study, we found that asking people to estimate the calorie content of foods reduced self-reported confidence in their ability to judge the health of these foods—which allowed them to rate these foods more moderately. We observed the effects of calories, but did not observe other nutritional indicators such as fat or carbohydrates, which consumers tend to see as less familiar.

This pattern was repeated in our experiments. Instead of helping people improve their assessments, calorie information creates what researchers call metacognitive uncertainty, or a “feeling of what I think I understand, but now I’m not sure.” When people are unconvincing about their understanding, they tend to avoid extreme judgments.

[embed]https://www.youtube.com/watch?v=veqah4lrouo[/embed]

Because people often see calorie information, they think they know how to use it effectively. But these findings suggest that a very familiarity of calorie counts can backfire, creating a misunderstanding that can lead to more confusion than less. My co-author and I call it a calorie fluent fantasy. When people are asked to judge the health of food based on calorie data, confidence quickly disappears and their health judgments become inaccurate.

Why it matters

These findings are of great significance to public health and businesses investing in calorie transparency. Public health policies assume that providing calorie information will drive more wise choices. But our research shows that visibility is not enough - calorie information alone may not help. In some cases, it may even lead to people making fewer healthy choices.

This does not mean that calorie information should be removed. Instead, it needs to be supported with more context and clarity. One possible approach is to pair calorie figures with decision aids such as traffic light indicators or overall nutrition scores, both of which exist in certain European countries. Additionally, calorie information about the item may be accompanied by clear reference points to illustrate how many calories a person recommends for daily calories – although this can be challenging, as there are a variety of calorie requirements every day.

Our research highlights a broader problem in healthy communication: Just because information is available does not mean it is useful. Realizing that calorie information seems easier to understand than it actually is, can help consumers make smarter, confident decisions about their diet.

Don't know yet

In our research, we found that calorie information was particularly prone to a fantasy of understanding. But the key issues still exist.

For example, researchers don’t know how this hallucination can interact with growing health and wellness applications, personalized nutrition tools, or AI-based food recommendations. Future research could look at whether these tools can really help people to be more certain of their choices, or just make them feel confident without really understanding the information.

A brief introduction to the research is a brief view of interesting academic work.