Why did the scientific necessity for the term chlorosis dissolve in the early 20th century?

Answer

Researchers understood the molecular role of iron in hemoglobin synthesis

As hematology advanced, the medical community gained an understanding of the specific molecular mechanics behind anemia. Once it was established that the condition was fundamentally caused by an iron shortage and that this could be objectively measured and treated with iron, the need for a separate, vague, and socially loaded syndrome name disappeared. Medicine moved toward precise classification and targeted treatment of the underlying nutrient deficiency.

Why did the scientific necessity for the term chlorosis dissolve in the early 20th century?
humanchlorosisconditionsymptomanemia