Vitamin B12 Deficiency: Causes, Signs and Symptoms
Vitamins supplements are selling like hot-cakes nowadays. However, a significant proportion of consumers are merely driven by the notion that vitamins-are-required-for-a-good-health and have a very little idea of what they really are! Vitamins are a group of organic substances which cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. They are essential in small quantities for normal metabolism. There are different types of vitamins classified on the basis of their biological and chemical activity and vitamin B complex is one of them. Vitamin B12 has been associated with a lot of significant metabolic functions that may be impaired because of its deficiency. Vitamin B12, or cobalamine as it is chemically known, has been found to play an important role in regulation of the sleep-wake cycle by the pineal gland through melatonin. It is also known to assist in the formation of red blood cells and functioning of nervous system along with being a catalyst in the proper functioning of folic acid.
As vitamins are required to be provided exogenously, deficiencies of vitamins may arise due to restricted diets or inability to absorb or use certain vitamins due to inborn errors of metabolism or because of any of the life-style factors, for instance, Vitamin B12 is the only vitamin that is not found in vegetables and that makes strict vegans more susceptible to its deficiency. However, Vitamin B12 deficiency may be caused because of any of the various factors other than diet. For instance, Vitamin B12 is excreted into the liver and is passed into bowel where it is reabsorbed by intestines. So, Liver (and also pancreatic) damage may lead to vitamin B12 deficiency. Further, Crohn’s disease i.e. a progressive inflammation of the ileum producing frequent bouts of diarrhea, may also interfere with vitamin B12 absorption. As vitamins B12 is stored in significant amounts in the liver, a person on B12 deficient diet may not show any of the deficiency associated symptoms for many months!
In case of Vitamin B12 deficiency, early signs may include loss of appetite, diarrhea, numbness and tingling of hands and feet, paleness, tiredness and decreased concentration and memory. Sleep disturbances may also occur because of B12’s association with sleep-wake cycle. Various neurological and behavioral signs like disturbed coordination or cognitive functions may result because of the demyelination and irreversible death of neurons due to vitamin B12 deficiency. In a 1999 report published in Nutrition Reviews, Vitamin B12 deficiency has also been speculated to lead to breast cancer as it could result in less folate being available to ensure proper DNA replication and repair. Deficiency of vitamin B12 along with folate and B6 has also been reported to also cause reductions in brain capillary length and density. In case of Vitamin B12 deficiency, one of the most commonly observed symptoms is weakness and fatigue which may be explained by production of fewer, but larger RBCs with a decreased oxygen carrying capacity causing a medical condition called macrocytic anemia.
Although awareness levels are increasing and nutritional supplements are increasingly becoming popular, but still, research is far from complete and all that can be said with certainty is that – if you eat a balanced diet, go enjoy that football game; you don’t have to worry about vitamin deficiencies!