Investigating the ‘halo effect’ of food claims

Consumers often misguess the calorie content of food

Every day, we have to make lots of choices about what to eat, and thinking hard about each one would take too much time and effort. So, people naturally end up using ‘heuristics’ which are quick and easy ways to decide - even if these shortcuts might sometimes lead us to the wrong choice.

In our study published in the International Journal of Food Science & Technology, we investigated whether health-related messages on food packaging, such as nutrition claims (e.g. zero sugar and 0% fat), health claims (e.g. better gut health) and five-a-day claims, which are designed to help consumers make healthier food choices and eat a balanced diet, in fact have unintended consequences.

Specifically, the study investigates 'calorie illusion' - the common miscalculation in calorie content, influenced by various factors such as food labelling, health claims or the presence of healthy ingredients.

Further, the study examines the ‘halo effect’ – a phenomenon where the perception of the positive attribute of one food product overshadows the judgment of the overall meal leading consumers to perceive it as being more nutritious, healthier, or lower in calories than it actually is.

The study focuses on these systematic biases when people estimate the calorie content of combinations of healthy food such as vegetables and unhealthy foods such as junk food in a single meal.

A survey of 525 participants from the UK, aged 18 to 80, revealed that less than one third of respondents consistently check the nutrition facts panel on food packaging. Additionally, just over 30 per cent indicated they are less inclined to review the nutrition facts panel if the product features a nutrition or health claim on the front, suggesting that such claims may deter consumers from scrutinizing the nutritional information provided on the packaging. This pattern suggests that front-of-package claims can potentially overshadow the detailed nutrition facts panel, leading to less informed dietary choices.

Regarding calorie content estimation, around 40 per cent of participants admitted to difficulties in accurately assessing the caloric content of foods. An 'averaging bias', where individuals average the calories content of combinations of food, was evident when respondents underestimated calories content for meals composed of both healthy and unhealthy items, confirming the calorie illusion phenomenon. Conversely, calories were consistently overestimated for meals containing exclusively unhealthy components.

Further, the presence of nutrition and health claims, like 'low-fat' or 'zero-sugar,' tend to lead people to guess that the number of calories is lower than it is, especially for foods that are not healthy. This finding suggests that while nutrition and health claims are designed to enhance the perceived healthiness of food products, they can also inadvertently lead to misconceptions about calorie content. This is due to a tendency among consumers to overgeneralize the nutritional quality of a diet, often assuming that foods labelled as healthier are always lower in calories.

Although guessing the calorie content and healthiness of food saves the time it would take to check the nutrition fact panel, the estimated calorie content and perception of nutrition is prone to errors.

These findings underscore the need for better consumer education on nutritional content. By emphasizing the importance of examining all nutritional information to consumers, rather than relying solely on highlighted claims, consumers can make more informed choices, leading to balanced healthy diets.

This is particularly crucial for those who might otherwise fall into the trap of 'health halos' - assuming that the presence of healthy foods like fruits and vegetables reduces the overall calorie count of a meal, which can inadvertently lead to overeating.

Food regulations could be stricter about how food is marketed, particularly when it comes to health and nutrition claims. There is a need for greater scrutiny, particularly on claims which are not covered by government schemes, to prevent calorie illusion from overstating the benefits of a food item.

The food industry should also commit to more transparent labelling regarding nutritional and health claims, ensuring that consumers receive clear and accurate information to make better dietary choices.

By Toju Begho

Posted by Toju Begho on 07/11/2023

Tags: Food and Drink
Categories: Research