Gastroenterologists W P Goddard and R C Long argue that gastrointestinal endoscopy should always be used in the diagnosis of iron deficiency anemia, as it allows visualization of small mucosal lesions, direct estimation of blood loss, and biopsy sampling, particularly from the second part of the duodenum for coeliac disease. They also emphasize the importance of colonoscopy over barium enema, though the latter can serve as a screening test in hospitals without a colonoscopist. The authors critique the article by Frewin et al., suggesting that their approach to iron deficiency anemia is superficial and that their recommendations for investigations, such as fecal occult blood testing, are inadequate. They highlight the need for comprehensive investigations, including screening for coeliac disease, and emphasize the importance of diagnosing the underlying cause of the anemia.Gastroenterologists W P Goddard and R C Long argue that gastrointestinal endoscopy should always be used in the diagnosis of iron deficiency anemia, as it allows visualization of small mucosal lesions, direct estimation of blood loss, and biopsy sampling, particularly from the second part of the duodenum for coeliac disease. They also emphasize the importance of colonoscopy over barium enema, though the latter can serve as a screening test in hospitals without a colonoscopist. The authors critique the article by Frewin et al., suggesting that their approach to iron deficiency anemia is superficial and that their recommendations for investigations, such as fecal occult blood testing, are inadequate. They highlight the need for comprehensive investigations, including screening for coeliac disease, and emphasize the importance of diagnosing the underlying cause of the anemia.