In countries where people eat more mollusks and crustaceans, fewer children have anemia, even when accounting for income levels, sanitation, and consumption of other animal-based foods.
Mechanism
Synthesis from 1 study
Mollusks and crustaceans give children the exact kinds of iron and vitamin B12 their bodies need to make healthy red blood cells, which carry oxygen. Other foods don’t provide these nutrients in forms that are as easy to absorb, so eating these seafoods helps prevent anemia more effectively.
Most probable mechanism
When children eat mollusks and crustaceans, their bodies absorb more usable iron and vitamin B12 than from plant foods. This iron is used to make hemoglobin, the protein in red blood cells that carries oxygen, and vitamin B12 helps those red blood cells form properly. Without enough of these two nutrients, red blood cells don’t develop right or don’t carry enough oxygen, leading to anemia. Eating these seafoods gives children the right nutrients in forms their bodies can use best, helping prevent anemia.
Heme iron from mollusks and crustaceans is absorbed efficiently through specialized transporters in the upper small intestine
Absorbed iron binds to transferrin and is delivered to bone marrow erythroblasts for incorporation into hemoglobin
Vitamin B12 from mollusks and crustaceans is absorbed in the ileum with intrinsic factor and acts as a cofactor in DNA synthesis pathways essential for red blood cell maturation
Deficiency in iron or vitamin B12 disrupts erythropoiesis, causing microcytic or megaloblastic anemia due to impaired hemoglobin production or abnormal red blood cell division
Adequate intake of bioavailable iron and vitamin B12 restores normal hemoglobin concentration and red blood cell morphology, reducing anemia prevalence
Less supported by current evidence, but not ruled out
Zinc helps the body fight infections and heal tissues, while DHA reduces inflammation. When children have enough of these nutrients, their bodies waste less energy fighting sickness and can use food better to make blood and grow.
Zinc from mollusks and crustaceans is absorbed in the small intestine and supports the function of over 300 enzymes involved in immune response and protein synthesis
Chronic inflammation from infections or poor sanitation impairs iron absorption and red blood cell production
DHA modulates inflammatory signaling pathways, reducing cytokine-driven suppression of erythropoiesis
Improved immune function and reduced inflammation enhance the efficiency of iron utilization and hemoglobin synthesis
Evidence from Studies
Supporting (1)
Community contributions welcome
Aquatic Animal Foods for Nutrition Security and Child Health
Contradicting (0)
Community contributions welcome
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