Cardiologist Dr. Dmitry Yaranov suggests salt is not universally harmful, emphasizing its essential role in bodily functions like nerve and muscle activity, and blood pressure regulation. He clarifies that while sodium is crucial for life, it can be detrimental for individuals with specific medical conditions, particularly cardiovascular disorders. Dr. Yaranov identifies five situations where patients should avoid or reduce salt intake, noting that for some, excess sodium can exacerbate existing diseases.