Deficiency of vitamin B12 causes cerebral atrophy

                               Deficiency of vitamin B12 causes cerebral atrophy

                                                    Nitin .K. Sethi, MD

                                            Assistant Professor of Neurology

                                            New York-Presbyterian Hospital

                                              Weill Cornell Medical Center

                                                New York, NY 10065

I am big on vitamins both when it comes to taking it myself and recommending it to my patients. So my interest was naturally piqued when I read an article in the journal Neurology titled ” Vitamin B12  status and rate of brain volume loss in community-dwelling elderly” by Vogiatzoglou et al. The authors investigated the relationship between markers of Vitamin B12 status and brain volume loss in an elderly population. They concluded that low levels of vitamin B12 may contribute to brain volume loss (cerebral atrophy) and may be one of the causes of subsequent cognitive impairment in this population. So how do we interpret this data?

Can vitamin B12 intake prevent the onset of dementia.?

 If so how much of this vitamin should one take?

And at what age should one start taking this?

Questions for which we still do not have good answers. As I see it, vitamin B12 is pretty innocuous (side-effects are few if any) and thus can be safely taken by the majority of people. Moreover it is cheap (as unlike some other vitamins and anti-oxidants in the market eg coenzyme Q10). Dementia is a devastating neurodegenerative condition for which at present there is no cure. If vitamin B12 intake prevents cerebral atrophy then it may be worthwhile recommending it to my patients.

The elderly are a vulnerable population group. Many times their diet is marginal and thus they are prone to having nutritional (vitamin) deficiencies.  Other vulnerable groups include alcoholics (people who drink heavily, usually have marginal diets and thus are prone to vitamin deficiencies), people who have conditions which prevent the body from absorbing vitamin B12 example pernicious anemia, those who have had bowel surgery, Crohn’s diseases, ulcerative colitis etc.

Vitamin B12 is present in meat including fish, poultry, eggs, milk, and milk products. It is important for neuronal function and also helps to maintain healthy red blood cells. So deficiency is more commonly seen in vegetarians especially those who do not have even milk or milk products. It is this group whom I feel shall surely benefit from vitamin B12 dietary supplementation.

At what age should one start taking Vitamin B12 is difficult to answer. Vitamin B12 is stored in the liver and so a person who eats a healthy diet should have ample reserves of this vitamin and does not need supplementation. I usually check the vitamin B12 status of my patients especially those who are elderly or suffering from a chronic medical condition. This can be done by a simple blood test. If they are deficient, I prescribe vitamin B12 (vitamin B12 comes in tablet form. In patients who have very low stores, we sometimes give them a shot of vitamin B12 intramuscularly).

As for the rest of us (“healthy” and not too old) what should we do? One way would be to take a tablet of multivitamin a day. Most good multivitamin combinations do have B12 in them. That is what I do!!!

” the mind is a wonderful thing and a healthy mind is truly beautiful”

Alcohol induced dementia/ alcoholic neurodegeneration

Continuing with the effects of alcohol on the brain, in this post I shall dicuss a frequently asked question by people who consume alcohol, does it cause neurodegeneration? Does alcohol kill neurons/ brain cells?

Let us discuss the entity called alcoholic cerebellar and cerebral degeneration. We now sufficient data to suggest that excessive consumption of alcohol does damage the brain.  Some parts of the brain are more specifically affected, these include the cerebellum. The cerebellum is the part of the brain which controls coordination, balance, gait as well has motor memory (memory for common motor actions performed by the brain). In the cerebellum are cells called the Purkinje cells which are selectively destroyed by alcohol ( the part of the cerebellum most commonly affected is the midline of the cerebellum between the two cerebellar hemispheres. This part is called the vermis of the cerebellum). So in alcoholic cerebellar degeneration we see vermian cerebellar atrophy in CT scan and MRI scans and also grossly if an autopsy is carried out).

So how does vermian atrophy present clinically?

Patients with alcoholic cerebellar degeneration have problems with gait and balance. Their coordination is off and they are prone to frequent falls (we have all seen the walk of a drunkard. While the clinical signs may not be so overt, on clinical examination we can usually pick up the signs of cerebellar dysfunction). Since these patients are prone to falls, they frequently land up in the ERs with head injuries (intracerebral hematoma, epidural and subdural hematoma). See my post on neurotrauma

Alcohol induced dementia: while this entity is not so well defined as alcoholic cerebellar degeneration, there is ample evidence to suggest that too much alcohol damages the cerebrum and can cause cognitive and memory problems. The thinking is that this is not entirely due to alcohol only. When someone abuses alcohol, he or she also does not consume a good diet and soon becomes deficient in essential nutrients and vitamins such as vitamin  B12 and folic acid. So alcohol induced cerebral degeneration is likely due to nutritional deficiencies.

No one quite knows the answer that if you supplement your diet with vitamins and essential nutrients even in the face of heavy and chronic alcohol consumption, would that prevent the development of alcoholic cerebral and cerebellar degeration. Infact in certain countries of the world a plan was put forward to fortify all alcoholic beverages with vitamins and essential nutrients. One of the problems with this proposal is that it alters the taste of the alcohol. Your rum does not taste like rum anymore!!!

In any case I advise my patients to always drink in moderation and to take 1to 2 tablets of a good multivitamin every day apart from a wholesome and nutritious diet.

Nitin Sethi, MD