Question

Provide a possible mechanism why folate can mask vitamin B12 deficiency.

Answer 1

Cyanocobalamin (vitamin B12) deficiency results in macrocytic, megaloblastic anaemia (pernicious anaemia) similar to folate deficiency.

functions of vitamin B 12 is needed for the manufacturing of red blood cells and DNA synthesis. helps to prevent mental deterioration and promotes growth.

Prolonged deficiency of vitamin B12 leads to nerve damage caused by the destruction of myelin sheath.

folate - cobalamin-methionine-homocysteine cycle

in this cycle, methyl from methylcobalamin is needed for the conversion of homocysteine to methionine.

In the absence of vitamin B 12, the cycle could not become complete, so the level of homocysteine get increased   .this is the elevated homocysteine in vitamin B 12 deficiency. And also affects RBC synthesis. ( 5 methyl tetrahydrofolate remain same in the absence of cobalamine- methyl folate trap).

If vitamin B12 deficient patient takes high dietary folate, the body can synthesise Red blood cells and DNA. folate can correct the shape of RBC and it looks normal. thus, folate can mask cobalamine deficiency.