Raw iron numbers tell only half the story. A cup of cooked spinach contains 6 mg of iron, but only 2–20% is absorbed—yielding 0.12–1.2 mg of usable iron. A 3 oz serving of beef contains just 2.5 mg of iron, yet 15–35% absorption delivers 0.375–0.875 mg of bioavailable iron. In practical terms, beef provides nearly equivalent nutritional iron benefit despite containing one-third the total iron content. This bioavailability gap reflects the distinct chemistry of heme versus non-heme iron and explains why nutritional recommendations cannot rely on label values alone. Clinically, this distinction becomes critical when counseling patients with anaemia who may consume iron-rich plant foods without achieving therapeutic benefit. Read the full article on GMJ Newsroom.
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