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Book

Vitamin B12 Deficiency

Alex Ankar  1 , Anil Kumar  2
In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan.
.
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Free Books & Documents
Book

Vitamin B12 Deficiency

Alex Ankar et al.
Free Books & Documents

Excerpt

Vitamin B12 (cobalamin) is a water-soluble vitamin that is derived from animal products such as red meat, dairy, and eggs. Intrinsic factor is a glycoprotein that is produced by parietal cells in the stomach and is necessary for the absorption of B12 in the terminal ileum. Once absorbed, B12 is used as a cofactor for enzymes that are involved in the synthesis of deoxyribonucleic acid (DNA), fatty acids, and myelin. As a result, B12 deficiency can lead to hematologic and neurologic symptoms. B12 is stored in excess in the liver; however, in cases in which B12 cannot be absorbed for a prolonged period (eg, dietary insufficiency, malabsorption, lack of intrinsic factor), hepatic stores are depleted, and deficiency occurs.

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Conflict of interest statement

Disclosure: Alex Ankar declares no relevant financial relationships with ineligible companies.

Disclosure: Anil Kumar declares no relevant financial relationships with ineligible companies.

References

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