It seems like you might be referring to a specific work of literature or a film in which a character named Nikolai's advises Lorenzo to stop eating certain foods. Without additional context or knowing the source material, I can't accurately identify the specific foods or the reasons for the recommendations.
If you provide the title of the book, film, or other source you're referring to, or some context about the story, I can help answer your question more specifically. Additionally, if this is a question about health or nutrition, I'm glad to discuss general dietary recommendations and why certain foods are often suggested to be avoided. Would that be helpful to you?