VITAMIN B12
An invisible epidemic of Vitamin B-12 deficiency is occurring in America. The lack of B-12 can cause megaloblastic anemia, nerve weakness, nerve numbness or tingling, chronic fatigue, dementia, coronary artery disease, depression, dizziness, multiple sclerosis symptoms, infertility, developmental delay in children and numerous other symptoms and diseases. If treatment of deficiency is started too late, many people suffer permanent neurological damage. Estimates of deficiency range from 9% in the general population, 15-20% in the elderly, 40% in hospitalized elderly and 50% of vegans.
Vitamin B-12 is the only vitamin that must be obtained from animal food sources. It has a complicated process of absorption that requires adequate stomach acid, intrinsic factor, pepsin, and intestinal receptors. If any part of the process is not functioning properly, Vitamin B-12 in food or in oral supplements will not be absorbed into the body.
Diagnosis of inadequate B-12 levels has traditionally been done with a blood level. Unfortunately, the test is plagued by false-positive and false-negative results. Low-normal B-12 levels are often ignored despite the person having symptoms typical of B-12 deficiency. Laboratory reference ranges typically run from 211-911. Levels below 350 can indicate a deficiency state and should be followed up by urinary MMA testing. High levels of folic acid (another B vitamin) can mask the underlying low levels of B-12 and give falsely elevated results. A newer test of methylmalonic acid in urine has been shown in research studies to be the most accurate test of B-12 status. Methylmalonic acid (MMA) in blood is a better test than blood B-12 levels but can be inaccurate in kidney diseases.
The elderly are particularly prone to suffer B-12 deficiency. Many have atrophic gastritis, a disorder of the stomach lining that causes low secretion of stomach acid. A very large number of people are taking acid blocking medications for heartburn and reflux. These people are also at risk for low B-12. Drugs known to cause low B-12 levels include diabetes drugs, potassium supplements, antacids, colchicine, and neomycin. Patients with gastric bypass surgery, ulcerative colitis or Crohn’s disease, celiac disease, and other causes of intestinal malabsorption are all at risk of low B-12.
Homocysteine is an amino acid that becomes elevated in B-12 deficiency. High levels are a major risk factor for heart attacks and strokes. Levels should be checked at least once to rule out a genetic predisposition to high levels. High levels can be lowered by taking folic acid, B-12 and B-6.
Treatment of a diagnosed B-12 deficiency should start with 3 to 5 shots of 1000 micrograms of B-12 the first week. Then give 4 weekly injections of 1000 micrograms. Lifelong maintenance injections of 1000 micrograms every month will prevent complications of deficiency. Unless detailed studies show that the B-12 deficient state is not due to poor absorption, it is better to utilize the reliable intramuscular injections. Vitamin B-12 injections are very safe and cheap. The preferred form of B-12 is the hydroxycobalamin. It is retained longer and is more effective than the commonly used cyanocobalamin. For neurologic symptoms, the methylcobalamin is preferred. This can be obtained from a compounding pharmacy. An excellent book on the topic of B-12 deficiency is "Could It Be B12? An Epidemic of Misdiagnosis" by Pacholok and Stuart.
Daniel Blodgett MD