Implicit and explicit safety evaluation of foods: The importance of food processing

Identifying beneficial foods in the environment, while avoiding ingesting something toxic, is an overlooked, yet crucial task humans face on a daily basis. Here we directly examined adults’ implicit and explicit safety evaluations of the same foods presented with different degrees of processing, ranging from unprocessed (raw) to processed (cut or cooked). Moreover, we investigated whether individuals’ characteristics (e.g., Body Mass Index, hunger, food neophobia) modulated their evaluations. We hypothesized that adults would associate the processed form of a food with safety more than its unprocessed form since processing techniques, which are ubiquitously applied in different cultures, often reduce the toxicity of foods and signal previous human intervention and intended consumption. Adults (N = 109, 43 females) performed an implicit Go/No-Go Association Task (GNAT) online, assessing the association between safety attributes (words associated with safety or toxicity) and food images differing on their degree of processing (unprocessed raw fruits and vegetables, the same foods cut-up and cooked into a puree); both unfamiliar and familiar foods were used. Then, each food was explicitly evaluated via Visual Analogue Scales (VAS). Results revealed that overweight and obese individuals rated cooked foods as the least safe overall at the explicit level (VAS results) while having a strong association between these processed foods and safety attributes at the implicit level (GNAT RTs results). Yet, at the explicit level, when looking at unfamiliar foods only, processed foods were rated safer than unprocessed foods by all participants (VAS results). Our results are the first evidence that directly highlights the relevance of the degree of processing in food safety evaluation and suggest that thinking of the important tasks humans face regarding food selection enriches our understanding of food behaviors.