beri beri is caused by lack of vitamin
Thiamine deficiency Thiamine deficiency, also known as beriberi, is a condition that occurs due to not enough thiamine (vitamin B1).[1] There are two main types: wet beriberi, and dry beriberi.[1] Wet beriberi results in a fast heart rate, shortness of breath, and leg swelling.[1] Dry beriberi results in numbness of the hands and feet, confusion, trouble moving the legs, and pain.[1] A form with loss of appetite and constipation may also occur.[3]
Parietal cell Parietal cells also produce intrinsic factor. Intrinsic factor is required for the absorption of vitamin B12 in the diet. A long-term deficiency in vitamin B12 can lead to megaloblastic anemia, characterized by large fragile erythrocytes. Pernicious anaemia results from autoimmune destruction of gastric parietal cells, precluding the synthesis of intrinsic factor and, by extension, absorption of Vitamin B12. Pernicious anemia also leads to megaloblastic anemia. Atrophic gastritis, particularly in the elderly, will cause an inability to absorb B12 and can lead to deficiencies such as decreased DNA synthesis and nucleotide metabolism in the bone marrow.