Food & Nutrition

Arab Journal of Food & Nutrition
120. Evaluation Of Vitamin B 12 Absorption amongVitamin B 12 Deficient Patients
and Investigation of a possible link of Vitamin B12 deficiency with oxidative
stress (2010)
Omar Majed Abuyaman\ University of Jordan
Supervisor: Dr. Yousif Y. Bilto
We investigated the causes of vitamin B 12 deficiency in relation to oxidative
stress and malabsorption in Jordan. B 12 deficient subjects suffered from increased
oxidative stress represented by significantly higher level of erythrocyte lipid
peroxidation among 22 B 12 deficient subjects (MDA mean=53.91nmol/g Hb)
compared to 53 normal B 12 subjects (MDA mean= 27.27 nmol/g Hb) and decreased
level of erythrocyte reduced glutathione among ٤٣ B 12 deficient subjects (mean=0.93
mg/g Hb) compared to 3٩ normal subjects (mean= 1.28 mg/g Hb). However, there was
no difference in the level of serum lipid peroxidation, serum and erythrocyte protein
oxidation, erythrocyte glutathione peroxidase and erythrocyte superoxide dismutase
between B 12 deficient and normal subjects. B 12 deficient subjects absorbed
significantly less amount of B 12 (active B 12 mean increase after 3.5 mcg oral B 12
doses=12.86 pmol/L) compared to normal B 12 subjects (24.15 pmol/L). Active B 12 test
was able to discriminate between the B 12 absorption of B 12 deficient and normal
subjects while the total B 12 test was not. The oral physiological dose of 3.5 mcg B 12
was better than the 14 mcg dose in the detection of mild malabsorption in the B 12
absorption test. In conclusion, B 12 deficiency seems to be linked somehow to oxidative
stress, but this study could not tell whether the B 12 deficiency leads to oxidative stress
or vice versa. Also, we were able to detect B 12 malabsorption among Jordanian B 12
deficient subjects, using a modified B 12 absorption test, as one cause of B 12 deficiency
in Jordan.
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Volume 11, No. 25, 2011
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