Home Alzheimer's and Dementia B Vitamins and Fish Oils Reduce Alzheimer’s Risk

B Vitamins and Fish Oils Reduce Alzheimer’s Risk


Homocysteine, B vitamins and reducing Alzheimer’s risk

In Alzheimer’s, the cerebral cortex is reduced, the brain shrinks (this is called cerebral atrophy) and the ventricles inside the brain grow larger.

These changes occur seven times more quickly in someone with Alzheimer’s than in a healthy person of the same age.

One identifiable factor in the lead up to Alzheimer’s is high levels of an amino acid, Homocysteine.

We have previously covered how homocysteine build up in the body is associated with both a higher risk of Alzheimer’s and cancer; and how research by an Oxford University team led by Professor David Smith showed how taking a daily B complex could prevent homocysteine build up and brain shrinkage. Certain B vitamins are known to be regulators of homocysteine and low levels of B-12 and folate have been linked to Alzheimer’s development (1).

Go To: Taking a daily B complex can prevent brain shrinkage and Alzheimer’s…

It is also known  that homocysteine can lead to histone blockages around your DNA, as it causes methylation increasing the bonding of histones to the DNA. In Alzheimer’s, homocysteine causes tangles in the brain structure according to Helga Refsum, Professor of Molecular Nutrition at the Institute of Basic Medical Sciences in Oslo.

Because of scientific queries over the first study linking B complex supplementation alone to both homocysteine and brain shrinkage reduction, a series of multi-country studies was undertaken:

In a first study – a randomized, controlled trial of B-12/B-6 supplementation vs a placebo, by Professor David Smith of Oxford University, the rate of brain atrophy was 53% lower in the group taking the B vitamins, and this mirrored the decline in homocysteine levels (2). Homocysteine build up has also been linked to cancer and heart failure.

This study was repeated by de Jager CA and others (3) with B vitamins showing a reduction of 30% in cognitive decline for those with already mild symptoms of Alzheimer’s  (over the control group).

B vitamins are made by your healthy gut bacteria as long as they are fed the correct foods. However as we age, the numbers of commensal (good) bacteria in our gut decline. And so does vitamin B production. It all makes sense.

First omega-3 levels need to be good, then folate, then B-12 makes a difference

Helga Refsum has highlighted that B-12 supplementation, if folate levels are already adequate, can be a preventative aid especially where mental impairment has already started to take place.

Other studies, for example by UC Davis Health, have shown links between gut bacteria, plaque formation and inflammatory attack (4).

But the study that pulled everything together came in 2015. In a collaborative study involving both David Smith and Helga Refsum, research showed a strong synergystic effect between omega-3 and B vitamins in both reducing homocysteine levels and reducing rates of cognitive decline (5). Where people had low omega-3 levels, B vitamins had no effect; but when omega-3 levels were high, B vitamins reduced cerebral atrophy by 40%.

Rainbow Diet Prevents Alzheimer’s

Prevention strategies are essential for dementia and Alzheimer’s, since ‘treatment drugs’ continue to fail in clinical trials.

In response to yet another such failure 11 top UK doctors wrote an open letter to UK Prime Minister David Cameron, urging him to adopt a colourful Mediterranean diet as the norm in the UK. To quote: “The evidence base for the colourful Mediterranean diet in preventing all of the chronic illnesses plaguing the Western world is overwhelming”.

Click on the book to read reviews and buy….

We have covered the consumption of fish and fish oil (long-chain omega-3) supplementation and the huge benefits in Alzheimer’s prevention elsewhere on this website.

Go to: Fish oils prevent Alzheimer’s

As we have told people frequently, people rarely eat enough oily fish, making daily fish or krill oil supplementation essential in the Western World.

Go to: Chris Woollams’ Super Krill oil – ‘clean’ Antarctica krill, formulated to be the maximum strength permitted under EU law; and with astaxanthin.


1.    http://www.ncbi.nlm.nih.gov/pubmed/11342684

2.    http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0012244

3.    http://www.ncbi.nlm.nih.gov/pubmed/21780182

4.    http://www.ucdmc.ucdavis.edu/welcome/features/20090909_Alzheimers/

5.     2015 Jul;102(1):215-21. doi: 10.3945/ajcn.114.103283. Epub 2015 Apr 15.