Prominent large language models, such as OpenAI's Chat Generative Pre-trained Transformer (ChatGPT), have shown promising implementation in the field of nutrition. Special care should be taken when using ChatGPT to prescribe protein-restricted diets for kidney-impaired patients. The objective of the current study is to simulate a chronic kidney disease (CKD) patient and evaluate the capabilities of ChatGPT in the context of dietary prescription, with a focus on protein contents of the diet.