Usability of a Chatbot for Health Promotion in Adults Over 40 Years Without a Diagnosis of Chronic Disease

Abstract

Objective: This study aimed to evaluate the acceptability and usability of the Nutribot tool among Peruvian adults aged 40 years or older without a diagnosis of noncommunicable diseases (NCDs), with the purpose of validating its relevance as a preventive educational resource and laying the groundwork for its large-scale implementation in public health. Material and Methods: The study included 50 participants who interacted with the system for 20–30 minutes and completed a usability questionnaire and one open-ended question. More than 60% of participants agreed or strongly agreed with key items (ease of use, clarity, comprehension, and usefulness). The likelihood of recommendation was high, with a mean score of 8.92/10 (median: 9; range: 6–10), indicating high overall satisfaction. Results: Participants’ ages ranged from 40 to 83 years, with no appreciable differences in ratings across age groups. Qualitative analysis highlighted the speed, clarity, and user-friendly nature of the responses, as well as their practical usefulness in everyday consultations. Key suggestions included the need for greater system proactivity and improved information presentation through more structured formats and additional functionalities. Conclusions: The findings demonstrate the feasibility of implementing an LLM-based nutritional chatbot delivered via WhatsApp as a complementary tool to promote healthy lifestyles and self-management of well-being among adults. Additionally, the study provides operational evidence to optimize the prototype prior to large-scale public health deployment.