Important findings of B-12

Vitamin B12:
Vital Nutrient for Good Health

By Sally Fallon and Mary G. Enig, PhD

"Vitamin B12 works with folic acid in many body processes including synthesis of DNA, red blood cells and the insulation sheath (the myelin sheath) that surrounds nerve cells and facilitates the conduction of signals in the nervous system. Severe depletion manifests as pernicious anemia, which was invariably fatal until the discovery of B12 in liver. But long before anemia sets in, other conditions may manifest, most often neurological problems (numbness, pins and needles sensations, a burning feeling in the feet, shaking, muscle fatigue, sleep disorders, memory loss, irrational anger, impaired mental function and Alzheimer’s) or psychological conditions (dementia, depression, psychosis and obsessive-compulsive behavior).

"Because the absorption process is so complicated, and therefore subject to various blocks, many people--particularly the elderly--may develop deficiencies even though they are taking in plentiful B12 in their food. Fortunately, the body absorbs about 1-5 percent of free B12 by a process of passive diffusion. Thus supplementation with large doses of crystalline B12 or with foods extremely rich in B12 can successfully treat deficiencies caused by compromised protein digestion or lack of R-protein, intrinsic factor or pancreatic enzymes. Supplementation with the coenzyme forms methylcobalamin and adenosylcobalamin (the forms found in the cells) can overcome B12 deficiency in the cells caused by lack of, or malfunction of, conversion enzymes.

B12 is found almost exclusively in animal foods such as liver, kidney, meat, fish, shellfish, milk products and eggs but the original source of B12 in nature is bacteria, the only creatures able to manufacture this vitamin. In humans and animals, these bacteria produce B12 in the colon; however, little if any is absorbed across the colon wall so we must get our B12 from animal foods. Bivalves such as clams, mussels and oysters contain high levels of B12 because they siphon large quantities of vitamin B12-synthesizing microorganisms from the sea.³ Production of B12 supplements involves fermentation procedures similar to those used for penicillin and other antibiotics.

[Patient has a known allergy to penicillin]

"A surprising source of cobamides is bacterial overgrowth in the small intestines, which can produce B12 analogs.¹³ The use of antibiotics, or a diet high in refined carbohydrates, can encourage the proliferation of bacterial overgrowth and lead to B12 deficiencies.

"Yet another area for concern is multivitamin products! The late Victor Herbert, a noted B12 researcher, maintains that many multivitamin products contain spurious and even dangerous analogs of B12 possibly formed when crystalline B12 interacts with other nutrients in multivitamin products, such as vitamin C, iron and copper.¹⁴

"High levels of folic acid can accelerate neuropsychiatric complications in persons with B12 deficiency.¹⁵ Since folic acid intakes of vegetarians tend to be high (from green vegetables and from grain products that have been fortified with folic acid), those following a vegetarian lifestyle may be at increased risk of neurological and psychological problems.

"The body stores considerable B12 in the liver. Thus a delay of 5-10 years may separate the beginning of a vegetarian diet (or absorption problems) and the onset of deficiency symptoms. Interestingly, the body can recycle over 75 percent of the B12 it uses.¹⁶ Used B12 is excreted in bile and then reabsorbed in the small intestine by the same complex process described earlier. Some people have a more efficient recycling system than others and hence can go longer on a vegetarian diet without signs of deficiency. However, more B12 is excreted in the presence of high levels of fiber, a common feature of vegetarian diets.¹⁷

MEASURING B₁₂ DEFICIENCY

"American medical opinion defines blood levels lower than 200 pg/mL as an indication of deficiency. This number is based on the level associated with the most severe manifestation of deficiency, pernicious anemia. In contrast, the lower limit in Japan and some European countries is 500-550 pg/mL, the levels associated with psychological and behavioral manifestations such as dementia and memory loss. Physicians in these countries consider blood levels of 500-1300 to be the normal range.¹⁹

"According to Dr. John Dommisse, an expert in B12 deficiency, the acceptance of high levels as normal in Japan, and the willingness to readily treat psychiatric symptoms with B12 explains the low rates of Alzheimer’s dementia in that country--as well as the reason for the very high rates of Alzheimer’s in the US.²⁰

"Even with the very low cutoff currently considered the risk point, large numbers of Americans are deficient. In the ongoing Framingham Offspring Study, involving 3000 men and women in the town of Framingham, Massachusetts, researchers found that 39 percent had B12 levels in the so-called "low normal" range, that is below 258.²¹ Had the researchers chosen the optimal range of 1100-1300 as a measure of B12 status, very few would have qualified as B12 replete.

"One of the most surprising findings of this study was the fact that the youngest group (26 to 49 years old) had about the same B12 status as the oldest group (65 and up), an indication that deficiencies are becoming more common.

SYMPTOMS OF AGING

"B12 deficiency mimics many of the features of old age--ataxia (shaky movements and unsteady gait) muscle weakness, spasticity, incontinence, slowed reactions, memory loss, disorientation, depression and confusion can all occur when B12 levels are low.

"Whether or not Alzheimer’s disease constitutes a condition of B12 deficiency is the subject of considerable debate among physicians. A recent and fascinating study of a family in Wales provides convincing evidence that low levels of B12 and Alzheimer’s are linked.²²

"Research shows tremendous potential for B12 to reverse mental decline in elderly patients. In one study, 61 percent of patients with mental impairment had complete recovery with supplementation; investigators speculate that those that did not recover had suffered from deficiency so long that damage to the nervous system had become irreversible.²⁴²⁵ Thus, routine early testing for B12 has the potential to prevent mental decline in the vast proportion of the elderly. By the time Alzheimer’s is conclusively diagnosed, it may be too late for supplementation to be effective. Supplementation results in little improvement for those who have had full blown Alzheimer’s symptoms for greater than six months.

NERVOUS DISORDERS

"One condition that would seem obviously correlated with B12 deficiency is multiple sclerosis (MS), a disease characterized by demyelination of the central nervous system. Yet many studies indicate that those with MS have normal blood levels of the vitamin. Japanese researchers have found that in MS patients, there is a decrease in the binding capacity of B12, thus inhibiting the transport of B12 into the cells, even in patients with normal levels in their blood.³³ Even so, they were able to achieve some improvement with high-dose supplementation.

"The benefit of B12 for depression may be due to B12’s ability to activate a substance called tetrahydrobiopterin (BH4), a compound which in turn helps activate "feel good" neurotransmitters like serotonin and dopamine.³⁴
Surprisingly, B12 has also proven successful in treating diabetic neuropathy, possibly because the condition of diabetes deranges B12 metabolism.³⁵

"Recurrent seizures may be a manifestation of B12 deficiency. One study found that individuals who suffered from seizures had low B12 levels.³⁶

Other neurological problems associated with B12 deficiency include urinary incontinence³⁷ and migraine headaches.³⁸ In one case history, B12 worked better than steroids as a treatment for Bell’s palsy.³⁹ Another case study reports that shaky leg syndrome responds well to B12 injections.⁴⁰

AN EXCEPTION TO OUR RULE

"In these pages, we have consistently advised obtaining vitamins from food (including superfoods) rather than with vitamin supplements. One good reason to avoid supplements derives from research indicating that they can interfere with B12 uptake, exacerbate the symptoms of B12 deficiency or even cause the creation of B12 analogs that increase the body’s need for B12.

"However, when it comes to B12 itself, supplementation with isolated B12 is often necessary and appropriate. The many factors in our modern lifestlye that block the complicated uptake pathways of this important nutrient--from nutrient deficiencies to exposure to toxins to factors in processed foods that cause reduced stomach acid, autoimmune disease and enzyme disruption--make it difficult to obtain sufficient quantities from our normal diet; and since vitamin B12 in supplements is produced in exactly the same way as B12 in nature, that is, by bacterial fermentation, the danger of high doses in most cases is negligible.

The authors wish to acknowledge the contribution of Lee Clifford, MS, CCN, for providing her extensive files on vitamin B12.

http://www.westonaprice.org/basicnutrition/vitaminb12.html