By Dr. Mercola

People who consume foods rich in vitamin B12 could be at lower risk of developing Alzheimer's disease.

Researchers analyzed blood samples from more than 270 individuals who showed no evidence of dementia. They tested for levels of vitamin B12 and for levels of homocysteine, an amino acid that has been linked to an increased risk of Alzheimer's disease, and then tracked the study participants for seven years.

Each unit increase in vitamin B12 reduced the risk of developing Alzheimer's by 2 percent.

According to CNN:

"The relationship between vitamin B12 and Alzheimer's risk is 'complex' ... B12 levels, particularly holotranscobalamin levels, likely play a contributory role."


  CNN October 18, 2010

  Neurology October 19, 2010;75(16):1402-3


Dr. Mercola's Comments:


You may not realize it but we are clearly in the middle of an Alzheimer's epidemic. According to the Alzheimer's Disease Facts and Figures report for 2009, 5.3 million people in the U. S. have the disease, and it has become the sixth leading cause of death in this country.

In the next 20 years it is projected that Alzheimer's will affect one in four Americans. If that turns out to be true, it would then be more prevalent than obesity and diabetes is today!

Can you imagine? The social and economic ramifications of this would be mind-boggling. There's no doubt we must start paying careful attention to this issue now in order to reverse the trend.

Mild cognitive impairment (MCI) is frequently the prelude to Alzheimer's. MCI currently affects around 16 percent of people over the age of 70, worldwide, and about half of all people diagnosed with MCI deteriorate into Alzheimer's disease within five years.

Whereas MCI typically does not interfere with daily life, Alzheimer's is a different story altogether. It's a 'mind-wasting' disease that can shatter entire families. Worse yet, there are very few treatments and there is no known cure.The primary treatment strategy currently employed by conventional medicine is drugs. Unfortunately, drugs such as Aricept, Exelon and Reminyl, may do more harm than good. This class of drugs is known to provoke slower heart rates, significantly increasing your chances of getting a permanent pacemaker, as well as increasing your risk of hip fracture.

That leaves you with just one solid solution, and that is to prevent it from happening to you in the first place.

Fortunately, this is within your power. I'm convinced that it is highly unlikely that I will ever develop Alzheimer's, for example, because my lifestyle prevents it, and I'll share my best recommendations at the end of this article.

But first, let's take a look at what researchers have discovered about the importance of B vitamins to help prevent this disease.

Dietary B12 for Optimal Brain Health

According to a small Finnish study recently published in the journal Neurology, people who consume foods rich in B12 may reduce their risk of Alzheimer's in their later years.

For each unit increase in the marker of vitamin B12 (holotranscobalamin) the risk of developing Alzheimer's was reduced by 2 percent.

However, I strongly disagree with the dietary advice published by CNN Health, which included fish and fortified cereals.

Fortified cerealsare most definitely NOT a good source of dietary B vitamins. They also have inorganic iron added. This is the worst type of iron to use as a supplement and it will raise already elevated iron in those that don't need it, like most adult men and postmenopausal women. Elevated iron levels will actually increase your risk of Alzheimer's

Additionally, most fish are today so contaminated, I cannot recommend increasing consumption of fish either. One exception would be sardines, which are high in B12 and small enough to typically be less contaminated, compared to larger fish.

Instead, your ideal dietary sources of B12 vitamins would include:

  • Liver from organic calf
  • Wild caught salmon
  • Organic, grass-fed beef
  • Lamb (which are typically grass-fed even if not specified as organic)
  • Organic, free-range eggs

Vitamin B12 is present in natural form only in animal sources of food, which is one of the reasons I advise against a strict vegetarian or vegan diet. The few plant foods that are sources of B12 are actually B12 analogs. An analog is a substance that blocks the uptake of true B12, so your body's need for the nutrient actually increases.

There are many well-documented cases of blindness and brain abnormalitiesin strict vegetarians, resulting from vitamin B12 deficiency.

Results Using Synthetic B Vitamins are Mixed...

I want to mention two additional studies published this year, mainly because they illustrate the mixed results achieved with vitamin B supplements (as opposed to a vitamin B-rich diet).

An Australian study published in Septemberinvestigated whether or not supplements, as opposed to food, could help older men improve their cognitive function. All the study participants were hypertensive men over the age of 75.

The men received either folic acid along with vitamin B6 and B12, or a placebo for two years. Their cognitive function was evaluated for another eight years thereafter.

In this case, the vitamin supplementation had no impact on cognitive function, and did not reduce the risk of dementia. The authors concluded:

"This study provides Class I evidence that vitamin supplementation with daily doses of 400 μg of B12, 2 mg of folic acid, and 25 mg of B6 over 2 years does not improve cognitive function in hypertensive men aged 75 and older."

Contrast this with another recent study published in PLoS One, in which the participants received very high doses of B vitamins. This two-year long clinical trial was the largest to date to investigate the effect of B vitamins on mild cognitive impairment (MCI), which, as I stated earlier, is a common precursor to Alzheimer's.

The vitamin pills, which are so potent you can only obtain them with a prescription, contained:

  • 800 micrograms (mcg) folic acid -- US RDA is 400 mcg/day
  • 500 mcg B12 (cyanocobalamin) – US RDA is only 2.4 mcg/day
  • 20 mg B6 (pyridoxine hydrochloride) -- US RDA 1.3-1.5 mg/day

In this study, the participants who received the vitamin supplements had half the rate of brain atrophy (shrinkage) associated with dementia, compared to those who did not receive supplementation. And those with the lowest B12 levels had a six-fold greater rate of brain volume loss compared with those who had the highest levels!

According to one of the co-authors:

"This is a very dramatic and striking result. It's much more than we could have predicted… It is our hope that this simple and safe treatment will delay development of Alzheimer's in many people who suffer from mild memory problems."

So, although the verdict is still out on whether or not you can prevent Alzheimer's using supplements, it certainly makes good sense to make sure you're getting plenty of complex B vitamins through your diet.

What You Need to Know About Vitamin B12 Supplements

That said, should you decide to boost your B12 intake with a supplement, please be aware that oral or sublingual B12 tablets do not work very well, so you may be wasting your money.

Injectable B12 is considered the gold standard, but sublingual sprays are just as effective as the injectable versions. They're also more convenient, not to mention less painful to use.

Risk Factors for Alzheimer's

Researchers have determined that the primary genetic risk factor is the presence of the Apo lipoprotein E epsilon4 (APOE e4) allele, which is more common among Africans, Inuits, Amerindians, Northern Europeans than southern Europeans.

But genetics cannot account for the vast majority of Alzheimer's cases.

There is definitely something else affecting us and inducing these devastating effects...

Although we do not have definitive "proof" of what, specifically, causes Alzheimer's, a number of factors have been linked to an increased risk of dementia, and we know enough about those to in turn make educated recommendations for preventing this type of brain deterioration.

Following are a number of risk factors associated with an increased risk of Alzheimer's disease. For further information about each of them, please follow the links provided:

Health conditions:

  1. Obesity, especially increased belly fat
  2. Insulin resistance and diabetes– Diabetics have up to 65 percent higher risk of developing Alzheimer's disease
  3. Elevated uric acid levels
  4. High blood pressure
  5. Thyroid dysfunction
  6. Intracellular T3 (immune system cells) deficiency
  7. Heart disease

Nutritional deficiencies:

  1. Vitamin D deficiency
  2. Elevated homocysteine levels due to vitamin B6, B12 and folate deficiencies
  3. Insufficient omega-3 fats
  4. Vitamin E deficiency

Environmental toxins:

  1. Aluminum toxicity
  2. Mercury toxicity
  3. Fluoride
  4. Copper toxicity
  5. Electromagnetic fields and cell phone radiation -- Henry Lai and Narendra Singh's research on the effects of cell phone radiation on rats' brains found DNA breaksassociated with cancer and Alzheimer's.  

Of these factors, the one I believe is perhaps the most important is insulin resistance. Some are even referring to Alzheimer's as the third form of diabetes.

A close tie would be vitamin D deficiency, which is also rampant across the world and underlies many chronic diseases, including dementia according to recent findings.

As for insulin resistance, it's a major factor in elevating your blood pressure, as well as for gaining excess weight; elevating your lipids, blood sugar and uric acid levels; and developing heart disease – all of which are risk factors for dementia.

So, if you are producing too much insulin, you're going to be at risk for all of these health problems—along with brain atrophy and Alzheimer's as well.

Once you begin to see the spiral cause and effect relationships between these common health problems and nutritional deficiencies, it becomes easier to understand how you can prevent nearly ALL disease, including something as tricky as Alzheimer's.

Preventing Alzheimer's – Naturally!

While effectively preventing associated health risks, such as obesity, insulin resistance, high blood pressure and heart disease, these simple lifestyle changes can also help keep your brain in optimal working order well past your 60's.

  • Coconut oil -According to Dr. Mary Newport, D.M, whose husband was stricken with Alzheimer's disease, coconut oil may be KEY for not only preventing, but even reversing this disease. Certain cells in the brains of those with Alzheimer's become increasingly unable to use their primary energy souce, glucose. Without fuel, these brain cells die, contributing to the mental degeneration. But there's an alternative source of energy, known as ketones. Your body produces ketones naturally when you deprive it of carbohydrates (which further supports the recommendation to eliminate sugar and grains from your diet!), but you can boost ketone production by consuming medium-chain triglycerides, such as coconut oil.

Dr. Newport made this connection when she discovered that the ingredient in a promising Alzheimer drug was nothing more than simple coconut oil-derived medium-chain triglycerides! Beneficial results were obtained at a dose of about 20 ml (4 teaspoons).

  • Optimize your vitamin D levels through safe sun exposure, a safe tanning bed and/or vitamin D3 supplements.

through safe sun exposure, a safe tanning bed and/or vitamin D3 supplements.

  1. Eat a nutritious diet, rich in folate. Ideally you'll want to design your diet around your nutritional type. Everyone, however, regardless of nutritional type will want to avoid fructose as much as possible.

Strict vegetarian dietshave been shown to increase your Alzheimer's risk, whereas diets high in omega-3's lower your risk.However, vegetables, without question, are your best form of folate, and we should all eat plenty of fresh raw veggies every day.

  1. Eat plenty of high-quality animal based omega-3 fats, such as krill oil. I recommend avoiding most fish, however, because although fish is naturally high in omega-3, most fish stocks are now severely contaminated with mercury.

High intake of the omega-3 fatty acid DHA helps by preventing cell damage caused by Alzheimer's disease, thereby slowing down its progression, and lowering your risk of developing the disorder. Researchers have also said DHA "dramatically reduces the impact of the Alzheimer's gene."

  • Keep your fasting insulin levels below 3. There is no question that insulin resistance is one of the most pervasive influences on brain damage, as it contributes massively to inflammation, which will prematurely degenerate your brain.
  • Avoid and remove mercury from your body. Dental amalgam fillings are one of the major sources of mercury, however you should be healthy prior to having them removed.

Once you have adjusted to following the diet described in my optimized nutrition plan, you can follow the mercury detox protocoland then find a biological dentist to have your amalgams removed. Please be careful as you could be jumping from the frying pan into the fire like I did if you see a conventional dentist to do the exchange. ONLY see a high quality biologically trained dentist, or your health could be seriously affected.

  • Avoid aluminum, such as antiperspirants, non-stick cookware, etc.
  • Exercise regularly.According to one study, the odds of developing Alzheimer's were nearly quadrupled in people who were less active during their leisure time, between the ages of 20 and 60. I would strongly recommend reviewing the Peak Fitness Technique for my specific recommendations.
  • Avoid flu vaccinations as most contain both mercury and aluminum!
  • Eat plenty of blueberries. Wild blueberries, which have high anthocyanin and antioxidant content, are known to guard against Alzheimer's and other neurological diseases.
  • Challenge your mind daily. Mental stimulation, especially learning something new, such as learning to play an instrument or a new language, is associated with a decreased risk of Alzheimer's. Researchers suspect that mental challenge helps to build up your brain, making it less susceptible to the lesions associated with Alzheimer's disease.
  • Avoid anticholinergic drugs. Drugs that block acetylcholine, a nervous system neurotransmitter, have been shown to increase your risk of dementia. These drugs include certain night-time pain relievers, antihistamines, sleep aids, certain antidepressants, medications to control incontinence, and certain narcotic pain relievers.

A recent study found that those who took drugs classified as 'definite anticholinergics' had a four times higher incidence of cognitive impairment. In those who were not carriers of the specific gene, APOE ε4 allele which I mentioned earlier in this article, the risk was over seven times higher.

Regularly taking two of these drugs further increased the risk of cognitive impairment.



KAY'S NOTE:  If you choose to use any of these suppliments, be sure they are SCD compliant.