Megaloblastic anaemia due to folic acid deficiency is commonly due to -
<p>Most dietary folate is present as polyglutamates;these are conveed to monoglutamate in the upper small intestine & actively transpoed into plasma.Plasma folate is loosely bound to plasma proteins such as proteins such as albumin & there is an enterohepatic circulation.Total body stores of folate are small & deficiency can occur in a matter of weeks</p><p>Serum folate is very insensitive to dietary intake; a single meal can normalise it in a patient with true folate deficiency.</p><p>Reference :Davidson&;s Principles & Practice of Medicine 22nd edition pg no1025</p>
Inadequate dietary intake
Defective intestinal absorption
Absence of folic acid binding protein in serum
Absence of glutamic acid in the Intestine
Haematology