There is growing evidence that a vitamin B12 deficiency, which affects an estimated one-quarter of North Americans, plays a major role in the onset of dementia.
If there is one disability that creates the greatest alarm for the baby boomer generation, it would be the loss of memory and brain functions. The concern is justified.
Alzheimer’s disease and other types of dementia now affect 97,000 Canadians, and by 2031 it is estimated that this number will rise to 750,000. Unfortunately, this is a worldwide trend with an estimated 24 million people presently diagnosed with dementia and an estimated 81 million predicted by 2040.
Are the various forms of dementia an inevitable consequence of aging or could they, in some instances, be symptomatic of an underlying (and overlooked) nutritional deficiency?
Effects of B12 deficiency
There is growing evidence that a vitamin B12 deficiency, which affects an estimated one-quarter of North Americans, plays a major role in the decline of neurological functions. B12 deficiency is more commonly found in the elderly and those with predisposing conditions such as Crohn’s disease.
Vitamin B12 (cobalamin), a fragile, water-soluble compound that performs a wide variety of functions in the body, is vital for good health. B12 is essential for normal nervous system function and normal red cell, white cell, and platelet production. A deficiency of B12, which may not be detected in a blood test, can result in neurological disorders often mimicking senility, dementia, or Alzheimer’s disease.
Causes of B12 deficiency
Diet, age, and drugs are the prime culprits behind B12 deficiency. The primary sources of vitamin B12 are meat, dairy, eggs, and fish. Inadequate intake of these foods or impaired absorption directly impacts B12 levels. A vegan diet will not provide adequate sources of B12.
It should also be noted that microwave cooking may inactivate vitamin B12. Researchers found that after just six minutes of microwaving, nearly half of the vitamin B12 in food was destroyed.
How B12 works
Vitamin B12 has the unique ability to provoke the regeneration of nerves without adverse side effects. This is because B12 facilitates methylation, the process that creates and maintains nerves and brain chemicals.
In addition, vitamin B12 is able to lower homocysteine levels. Homocysteine is a toxic byproduct of methionine metabolism that can damage neurons. Importantly, homocysteine interferes with the methylation reactions critical for brain function. By lowering homocysteine levels, neurological functions can be improved.
Vitamin B12 also protects brain health by helping in the synthesis of the neurotransmitters, serotonin, dopamine, and norepinephrine.
People who do not respond to supplemental vitamin B12 may also be deficient in folate. Since vitamin B12 and folate work synergistically to restore normal homocysteine levels, increasing folate may also be necessary.
In the past, vitamin B12 was administered by injections. However, oral B12 supplements have been found to be as good as or better than injections. While there are several forms of B12, methylcobalamin is the most neurologically active form. When taken sublingually (under the tongue), it is immediately assimilated into the brain.
A daily dose of 1,000 mcg of B12 is usually sufficient. However, if there is a deficiency then 2,000 mcg daily for one month is recommended, followed by 1,000 mcg daily.
There is little question that many people exhibiting symptoms of Alzheimer’s and other forms of dementia actually suffer from a vitamin B12 deficiency. For so many people, simply taking a B12 supplement could rescue them from the darkness.
Effects of dementia
While depression is a common symptom of early-stage dementia, the following can also be affected:
- motor skills
- short-term memory
- reaction time
- personality traits
- mood or behaviour
Who is at risk of B12 deficiency?
The elderly are most at risk of B12 deficiencies. There are several reasons for this:
- reduced production of intrinsic factor, a protein secreted by the stomach to help the body absorb B12
- low levels of hydrochloric acid, necessary for digesting proteins and maintaining intrinsic factor
- prescription and over-the-counter drugs for stomach ulcers, heartburn, or gastroesophageal reflux