Topic overview

Start with the big picture

The lesson reviews B1, B2, B3, B5, B6, B7, B9, B12, and vitamin C, pairing each vitamin’s active form or biochemical role with characteristic deficiency findings. It highlights distinctions with clinical value: B9 and B12 deficiencies can both cause megaloblastic anemia, but B12 deficiency is also associated with neuropathy and increased methylmalonic acid. Folate and B12 also differ in storage and absorption requirements. Most water-soluble vitamins are not stored in significant amounts, while B12 stores last for years and folate stores are limited. Alcoholism, malabsorption, and bariatric surgery are noted as contexts linked to deficiency.